sundance-communications.com/forum Forums Other TDM Phone Systems Sprint - Tadiran Telephones & Systems Extension Transfer

I have a Sprint Protege KSU with SVP-4 VM. I just added some DDEI cards, which worked great to exspan the system. The problem now is with any extension in the 300 range the first time someone from an outside call calls in and presses 3 the attend saids that you entered an incorrect digit. But if you enter the extension again it works. Any ideas??