Forwading features

I have a problem forwarding a call from sip to sip. WHat would be the dialplan config for this. Cause it uses the same t/g. Can I use another trunkgroup?Below is my dialplan config. Hope you could help me out on this. thanks.

exten=> 9998001,1,Dial(SIP/9998002,60,)
exten=> 9998001,n,Hangup

exten=> 9998002,1,Dial(SIP/9998003,60) ;anthony
exten=> 9998002,n,Hangup

exten=> 9998003,1,Dial(SIP/9998004,60) ;anthony
exten=> 9998003,n,Hangup

exten=> 9998004,1,Dial(SIP/9998004,60) ;anthony
exten=> 9998004,n,Hangup