Hi Manuel,
After some more testing I have realised that it seems to work fine on my developer machine (PHP 5.4.9), but it does not work on our production machine (PHP 5.3.23).
For easy testing, I isolated part of the code:
pastebin.com/G1CRZdAW
I've skipped the whole authentication part, but the tokens I enter are valid and work for any message that does not contain a '.
According to the php manual, not much changed to rawurlencode since 5.3.23; the tilde character is no longer encoded, but you fixed that anyway.
Is there any other feature of php that could have changed that I need to take a look at?
Many thanks,
Thijs