It doesn't work that way...
Packages are either 'sniffed', which means they are detected but not interfeared with, like used in NudgeBack, Open Convo Notifiers, etc, and all other scripts depending on a sniffer like Xniff.
Or either you create a 'proxy' which will sit between the internet connection and the client and thus can do whatever it wants with the recieved and sent packages.
Converting something to a string or whatever else does not intercept anything or does anything, it just converts it to a string.
quote:
Originally posted by CookieRevised
Only possible if you can make a proxy which intercepts and can change protocol messages. Or if you know where to patch messenger.
/ 
