Asterisk crashing because of IMAP (I'm pretty sure)

Hey everyone
I have been running asterisk for about 2 years, going through updates as they are released. Currently I am running 1.4.20, and it has been running strong up until a couple of days ago when I started using IMAP for voicemail storage.
My setup:
asterisk 1.4.20
imap-2007a
zimbra 5.0.6 <–separate server

This morning I logged onto my asterisk server, and reconnected to my console, noticing my verbose was turned off, normally I leave it at 6, did a core show uptime and it had only been running for 2 hours (thanks to init, it was restarted). So checking through my logs I see that a call came in, it was answered by the receptionist, (SIP/officewtg) and she transferred the call to wilma (SIP/wilma) she his the busy button and sent the call to voicemail, they left a message, and then asterisk crashed.

[Jun 23 08:57:35] VERBOSE[4648] logger.c:     -- Starting simple switch on 'Zap/4-1'
[Jun 23 08:57:35] VERBOSE[4648] logger.c:     -- Executing [s@incoming-wtg:1] Answer("Zap/4-1", "") in new stack
[Jun 23 08:57:35] VERBOSE[4648] logger.c:     -- Executing [s@incoming-wtg:2] Set("Zap/4-1", "CALLERID(all)="WTG"") in new stack
[Jun 23 08:57:35] VERBOSE[4648] logger.c:     -- Executing [s@incoming-wtg:3] MixMonitor("Zap/4-1", "20080623-085735-5889.wav") in new stack
[Jun 23 08:57:35] VERBOSE[4648] logger.c:     -- Executing [s@incoming-wtg:4] WaitExten("Zap/4-1", "2") in new stack
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- Timeout on Zap/4-1, continuing...
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- Executing [s@incoming-wtg:5] Dial("Zap/4-1", "SIP/daniellewtg&SIP/martywtg&SIP/foyerwtg&SIP/officewtg&SIP/cashdeskwtg&SIP/wilmawtg|30|t") in new stack
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- Called daniellewtg
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- Called martywtg
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- Called foyerwtg
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- Called officewtg
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- Called cashdeskwtg
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- Called wilmawtg
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- SIP/officewtg-083b3ad0 is ringing
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- SIP/daniellewtg-082c94b0 is ringing
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- SIP/martywtg-082599d8 is ringing
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- SIP/cashdeskwtg-085128f8 is ringing
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- SIP/foyerwtg-0822ce68 is ringing
[Jun 23 08:57:37] VERBOSE[4648] logger.c:     -- SIP/wilmawtg-08516870 is ringing
[Jun 23 08:57:41] VERBOSE[4648] logger.c:     -- SIP/officewtg-083b3ad0 answered Zap/4-1
[Jun 23 08:57:49] DTMF[4648] channel.c: DTMF begin '#' received on SIP/officewtg-083b3ad0
[Jun 23 08:57:49] DTMF[4648] channel.c: DTMF begin passthrough '#' on SIP/officewtg-083b3ad0
[Jun 23 08:57:49] DTMF[4648] channel.c: DTMF end '#' received on SIP/officewtg-083b3ad0, duration 220 ms
[Jun 23 08:57:49] DTMF[4648] channel.c: DTMF end accepted with begin '#' on SIP/officewtg-083b3ad0
[Jun 23 08:57:49] DTMF[4648] channel.c: DTMF end passthrough '#' on SIP/officewtg-083b3ad0
[Jun 23 08:57:49] VERBOSE[4648] logger.c:     -- Started music on hold, class 'default', on Zap/4-1
[Jun 23 08:57:49] VERBOSE[4648] logger.c:     -- <SIP/officewtg-083b3ad0> Playing 'pbx-transfer' (language 'en')
[Jun 23 08:57:50] DTMF[4648] channel.c: DTMF begin '5' received on SIP/officewtg-083b3ad0
[Jun 23 08:57:50] DTMF[4648] channel.c: DTMF begin ignored '5' on SIP/officewtg-083b3ad0
[Jun 23 08:57:50] DTMF[4648] channel.c: DTMF end '5' received on SIP/officewtg-083b3ad0, duration 210 ms
[Jun 23 08:57:50] DTMF[4648] channel.c: DTMF end passthrough '5' on SIP/officewtg-083b3ad0
[Jun 23 08:57:50] DTMF[4648] channel.c: DTMF begin '1' received on SIP/officewtg-083b3ad0
[Jun 23 08:57:50] DTMF[4648] channel.c: DTMF begin ignored '1' on SIP/officewtg-083b3ad0
[Jun 23 08:57:50] DTMF[4648] channel.c: DTMF end '1' received on SIP/officewtg-083b3ad0, duration 160 ms
[Jun 23 08:57:50] DTMF[4648] channel.c: DTMF end passthrough '1' on SIP/officewtg-083b3ad0
[Jun 23 08:57:51] DTMF[4648] channel.c: DTMF begin '0' received on SIP/officewtg-083b3ad0
[Jun 23 08:57:51] DTMF[4648] channel.c: DTMF begin ignored '0' on SIP/officewtg-083b3ad0
[Jun 23 08:57:51] DTMF[4648] channel.c: DTMF end '0' received on SIP/officewtg-083b3ad0, duration 210 ms
[Jun 23 08:57:51] DTMF[4648] channel.c: DTMF end passthrough '0' on SIP/officewtg-083b3ad0
[Jun 23 08:57:51] VERBOSE[4648] logger.c:     -- Stopped music on hold on Zap/4-1
[Jun 23 08:57:51] VERBOSE[4648] logger.c:     -- Executing Macro("Zap/4-1", "voicemail|SIP/wilma|30")
[Jun 23 08:57:51] VERBOSE[4648] logger.c:     -- Executing [s@macro-voicemail:1] Dial("Zap/4-1", "SIP/wilma|30|rt") in new stack
[Jun 23 08:57:51] VERBOSE[4648] logger.c:     -- Called wilma
[Jun 23 08:57:51] VERBOSE[4648] logger.c:     -- SIP/wilma-082013e8 is busy
[Jun 23 08:57:51] VERBOSE[4648] logger.c:   == Everyone is busy/congested at this time (1:1/0/0)
[Jun 23 08:57:51] VERBOSE[4648] logger.c:     -- Executing [s@macro-voicemail:2] Goto("Zap/4-1", "s-BUSY|1") in new stack
[Jun 23 08:57:51] VERBOSE[4648] logger.c:     -- Goto (macro-voicemail,s-BUSY,1)
[Jun 23 08:57:51] VERBOSE[4648] logger.c:     -- Executing [s-BUSY@macro-voicemail:1] VoiceMail("Zap/4-1", "510|b") in new stack
[Jun 23 08:57:52] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'vm-theperson' (language 'en')
[Jun 23 08:57:53] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'digits/5' (language 'en')
[Jun 23 08:57:54] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'digits/1' (language 'en')
[Jun 23 08:57:55] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'digits/0' (language 'en')
[Jun 23 08:57:55] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'vm-isonphone' (language 'en')
[Jun 23 08:57:57] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'vm-intro' (language 'en')
[Jun 23 08:58:02] WARNING[4648] app_voicemail.c: IMAP Warning: Bad quota root list for INBOX
[Jun 23 08:58:02] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'beep' (language 'en')
[Jun 23 08:58:03] VERBOSE[4648] logger.c:     -- Recording the message
[Jun 23 08:58:03] VERBOSE[4648] logger.c:     -- x=0, open writing:  /var/spool/asterisk/voicemail/internal/510/tmp/WdLkMj format: wav49, 0x8220258
[Jun 23 08:58:03] VERBOSE[4648] logger.c:     -- x=1, open writing:  /var/spool/asterisk/voicemail/internal/510/tmp/WdLkMj format: gsm, 0x82242c0
[Jun 23 08:58:03] VERBOSE[4648] logger.c:     -- x=2, open writing:  /var/spool/asterisk/voicemail/internal/510/tmp/WdLkMj format: wav, 0x8210548
[Jun 23 08:58:46] VERBOSE[4648] logger.c:     -- Recording automatically stopped after a silence of 10 seconds
[Jun 23 08:58:46] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'auth-thankyou' (language 'en')
[Jun 23 08:58:47] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'vm-review' (language 'en')
[Jun 23 08:58:48] WARNING[4648] file.c: Failed to write frame
[Jun 23 08:58:48] VERBOSE[4648] logger.c:     -- <Zap/4-1> Playing 'vm-goodbye' (language 'en')
[Jun 23 08:58:48] WARNING[4648] app_voicemail.c: IMAP Warning: Unexpected tagged response: 00020a30 OK SEARCH completed


Jun 23 08:58:50] NOTICE[4654] cdr.c: CDR simple logging enabled.
[Jun 23 08:58:50] NOTICE[4654] loader.c: 152 modules will be loaded.
[Jun 23 08:58:50] VERBOSE[4654] logger.c: .[Jun 23 08:58:50] VERBOSE[4654] logger.c: .[Jun 23 08:58:50] WARNING[4654] res_smdi.c: No SMDI interfaces are available to listen on, not starting SMDI listener.
[Jun 23 08:58:50] VERBOSE[4654] logger.c:  Loading [Sub]Agent Module
[Jun 23 08:58:50] VERBOSE[4654] logger.c: .[Jun 23 08:58:50] VERBOSE[4654] logger.c: .[Jun 23 08:58:50] VERBOSE[4654] logger.c: .[Jun 23 08:58:50] VERBOSE[4654] logger.c: .[Jun 23 08:58:50] VERBOSE[4654] logge
r.c: .[Jun 23 08:5

Anybody have ideas on what I can do to further debug this?
Thanks
-Eric

anybody? I have had to turn IMAP off because its crashing everytime somebody leave a voicemail.

Same problem. Asterisk = 1.4.20.1
IMAP = Zimbra 5.0.6
It’s been working fine for several weeks… then yesterday it froze on"IMAP Warning: Unexpected tagged response". System was restarted and worked fine for about 24 hours, then today the same thing occured.