PJSIP syntax for dialing a number with a + or *

With Asterisk 11 and SIP I am using the following AEL2 Dial command:

&trunkdial("SIP/obj-jch-trunk-obi/+${dialstring}",${DIAL_TIMEOUT_EXT},${DIAL_OPTIONS});

My OBi dials Google Voice if the number starts with a ‘+’ and an OBi number if it starts with a ‘*’.

I tried to do the same with PJSIP:

&trunkdial("PJSIP/+${dialstring}@obj-jch-trunk-obi",${DIAL_TIMEOUT_EXT},${DIAL_OPTIONS});

And it complains about the ‘+’, saying that +${dialstring} (with substitution of course) is not a valid URI.

Is there a way to make this work, or do I need to change the prefix from a ‘+’ or ‘*’ to a digit?

Thanks.

Jeff

What is the actual output from when it is attempted as well as your configuration?