Ypu’ll need to grab one of the Cisco IVR scripts or write your own in TCL.
Basically you upload the IVR script to the flash of the 5300 then add the line
call application voice
then in your dialpeer for the e1 you add the command
application
than all incomming calls ar run through the application.
Cisco have some good example ones that do most things people need. If not you’ll need to hire yourself a TCL programmer with a good knowlage of h323 and ISDN. 😉