Incoming call are answered by POTS-Provider (T-Com) as the number not available! The number dailed was correct! Also local numbers are redirected to a dial-peer withs is a fax on a FXS port (Dail-peer 3). No dial-peer redirection is configured with explance this behavior. Debug is on end confirms the problem. I have added the part of the config which is important. It seems that incoming calls which count 1 digit for the extension number are forward the the fax.
voice translation-rule 1
rule 1 /^30120$/ /50/
rule 2 /^\(3012\)\(..\)/ /\2/
voice translation-rule 10
rule 1 /\(^.+\)/ /00\1/ type national national
rule 2 /\(^.+\)/ /000\1/ type international international
rule 3 /\(^.+\)/ /00\1/ type any subscriber
voice translation-profile PSTN_IN
translate calling 10
translate called 1
dial-peer voice 50 pots (to dial-peer voice 53 pots)
description ** Anlagenanschluss 1 **
translation-profile incoming PSTN_IN
incoming called-number .