Search on here for a thread started by member funola - concerning the very same problem.
He rigged up a device (bamboo stick, IIRC?) and reached thru the first aid kit (removed) into the trunk and popped it open. Don't drill out the lock or break the tail-light until you absolutely have to (or have a spare tail-light on hand). Others have also suggest whacking the lock with a 2x4 and hammer - or vibrating the thing with a palm sander. Lots of info on here about this...
I was having issues with mine as well and did the same thing (reached in and unlocked it on my w123).....right now, the vac lock system is currently plugged with a golf tee, no more problems
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I don't have a trunk release either - haha....did you pull on your vac lines?
EDIT: member Howitzer has implanted all of us with this little tidbit - google is your friend.
http://www.peachparts.com/shopforum/showthread.php?t=194141