Follow-me and ringgroup no longer work

Hello,

I did a (what I thought) routine upgrade to Asterisk 1.6.2.18 yesterday, and since then, any extensions that use ring group or call forward no longer work. In all of those cases, asterisk comes to the conclusion that no one is answering (immediately so), and sends the call into the failover defined by freepbx (busy, drop, or voice mail).
The problem is, even with verbose and debug on 10, I do not see anything going wrong. It just comes to the conclusion that all of the extensions in the ringgroup or follow-me will not answer.
Here is an excerpt from the log:

[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:25] Set("SIP/sipconnect.sipgate.de-00000001", "CALLERID(number)=015777917425"$
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Set
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Function result is 'RS:xxxxxxxxxxxxxxxxxxxx'
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'Set'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:26] Set("SIP/sipconnect.sipgate.de-00000001", "CALLERID(name)=RS:xxxxxxxxxxxxxxxxxx"
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Set
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Macro
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Expression result is '1'
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Function result is 'g(1.2)'
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'Set'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:2] Set("SIP/sipconnect.sipgate.de-00000001", "VMGAIN=g(1.2)") in new stack
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Set
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'Macro'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:3] Macro("SIP/sipconnect.sipgate.de-00000001", "blkvm-check,") in new stack
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Function result is ''
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'Set'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:1] Set("SIP/sipconnect.sipgate.de-00000001", "GOSUB_RETVAL=") in new stack
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Set
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'MacroExit'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:2] MacroExit("SIP/sipconnect.sipgate.de-00000001", "") in new stack
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Macro
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Expression result is '1'
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'GotoIf'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:4] GotoIf("SIP/sipconnect.sipgate.de-00000001", "1?vmx,1") in new stack
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Goto (macro-vm,vmx,1)
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: GotoIf
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'Set'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:1] Set("SIP/sipconnect.sipgate.de-00000001", "MEXTEN=13") in new stack
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Set
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'Set'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:2] Set("SIP/sipconnect.sipgate.de-00000001", "MMODE=NOANSWER") in new stack
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Set
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Launching 'Set'
[Jun  1 11:31:54] VERBOSE[2189] pbx.c:     -- Executing [[email protected]:3] Set("SIP/sipconnect.sipgate.de-00000001", "RETVM=") in new stack
[Jun  1 11:31:54] DEBUG[2189] app_macro.c: Executed application: Set
[Jun  1 11:31:54] DEBUG[2189] pbx.c: Expression result is '0'

I am seriously scratching my head, as everything else works normally.
I hope someone here has an idea. I assume that under the hood, follow-me and ringgroup use the same code, so there is a fundamental problem?