Yes, from firmware 5.0 onwards it is possible to send variables of your phone via Action URLs to a remote Webserver.
Action URLs are basically HTTP "GET" requests and may contain variable names starting with $ and "pattern=$variable" strings separated by "&":

http://192.168.X.X/test.php?your_pattern1=$variable1&your_pattern2=$variable2&...

The execution is logged on the phone and can be easily verified on the phone´s  Log page:

[2]11/4/2006 10:52:43: Sending post request host = 192.168.X.X:80, file = /test.php?your_pattern1=$variable1

The following variables may be used for your own pattern:

• static variables: 
  • settings stored on the phone (Settings page)
  • Note: private settings e.g. passwords are replaced by empty strings
• runtime variables: 
  • $local for local URI (=own identity replaced at run-time)
  • $remote for remote URI (=caller ID replaced at run-time)
  • $call-id for the current call ID (replaced at run-time)

Examples:

http://192.168.X.X/test.php?language=$language
http://192.168.X.X/test.php?redirectnr=$redirect_number&redirecttime=$redirect_time
http://192.168.X.X/test.php?callingto=$remote&callingid=$local

Action URLs can be configured on the  Action URL setting page or the Function Keys page depending on the purpose:

1.Action URL setting page: Automatically based on the following events:

• DND on/off
• Redirection on/off
• Incoming call/Outgoing call
• Setup finished
• On offhook/onhook
• Missed call
• On Connected/Disconnected
  • Note: Those variables which are replaced on run-time do not work with all of these events.

2. Function Keys page: Manually by pressing the corresponding key.

• Context: Not used
• Key Event: "Action URL"
• Number: Action URL string