OK here the long version of the disconnect logging message in FHEM with verbose 5
2012.08.09 14:55:01 4: /fhem?cmd=get+CUL_0+version / RL: 1807 / text/html; charset=UTF-8 / /
2012.08.09 14:55:01 4: Connection closed for FHEMWEB:
192.168.22.21:338962012.08.09 15:00:01 4: Connection accepted from FHEMWEB:
192.168.22.21:338972012.08.09 15:00:01 4: HTTP FHEMWEB:
192.168.22.21:33897 GET /fhem?cmd=get+CUL_0+version
2012.08.09 15:00:01 5: Cmd: >get CUL_0 version<
2012.08.09 15:00:01 5: SW: V
2012.08.09 15:00:04 1: /dev/ttyACM0 disconnected, waiting to reappear
2012.08.09 15:00:09 5: Triggering CUL_0 (1 changes)
2012.08.09 15:00:09 5: CUL_0 trigger: Checking FileLog_CUL_EM_5 for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking FileLog_CUL_EM_6 for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking FileLog_CUL_EM_7 for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking Logfile for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking WEB for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking WEBphone for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking WEBtablet for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking autocreate for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking initialUsbCheck for notify
2012.08.09 15:00:09 5: CUL_0 trigger: Checking telnetPort for notify
2012.08.09 15:00:09 4: /fhem?cmd=get+CUL_0+version / RL: 1803 / text/html; charset=UTF-8 / /
2012.08.09 15:00:09 3: Setting CUL_0 baudrate to 38400
2012.08.09 15:00:09 1: /dev/ttyACM0 reappeared (CUL_0)
2012.08.09 15:00:09 5: SW: V
2012.08.09 15:00:09 5: CUL/RAW (ReadAnswer): V 1.46 CUL868