We have had this same problem.What solved the problem for us:Make sure that the called number is received at an DN that is under button 1.Then when you use 'CFWDall' you can route them to internal numbers.
/quoteip cef isdn switch-type basic-net3 ! ! voice rtp send-recv ! ! voice class codec 1 codec preference 1 g711alaw codec preference 2 g729r8 /quote.I don't have these options in my working config. It's almost the same es yours, so I would suggest y...