I can not reproduce this, the only time I do not get a transaction ID back in the response is when the transaction ID was not part of the command either:

(cmd) breakpoint_set -i 125 -t line -f file:///C:/udata-eclipse/testworkspaces/testxdebug/PhpCode/Looping.php -n 9 -- JGkgPT0gMTAw

<?xml version="1.0" encoding="iso-8859-1"?>
<response xmlns="urn:debugger_protocol_v1" xmlns:xdebug="http://xdebug.org/dbgp/xdebug&quot; command="breakpoint_set" transaction_id="125" id="21740001"></response>

(cmd) fsad

<?xml version="1.0" encoding="iso-8859-1"?>
<response xmlns="urn:debugger_protocol_v1" xmlns:xdebug="http://xdebug.org/dbgp/xdebug&quot; command="fsad"><error code="3"><message><![CDATA[invalid or missing options]]></message></error></response>

HI Derick, apologies, my output of the command was not correct, It turns out I was putting the transaction id at the end of the command ie
breakpoint_set -t line -f file:///C:/udata-eclipse/testworkspaces/testxdebug/PhpCode/Looping.php -n 9 -- JGkgPSAxMDA= -i 71

and so it wasn't picking up the transaction id, So I can fix this by putting the transaction id between the command and the command arguments (which are all the specific command arguments).

Don't know if you want to keep this open as xdebug didn't allow for arguments after the --.

Sorry about the confusion.

Okay, no worries. I'll close it then as this is not a bug. I did however find an invalid free problem with the condition which could make Xdebug crash when PHP was shutting down. I fixed that in CVS now.