String tokenizing in XSL

Greetings to all..

I am trying tokenize a string in XSL using str:tokenize. I want the delimiter to be taken as a combination of charactes. That is the tokenizing should occur only if combination of characters exist. (It should not tokenize if any of the characters in the delimiter is present individually)

For egs:

When I use str:tokenize('A%^B~^C%^D~^','~^') , I should get the output as A%^B and C%^D.

Is it possible with str:tokenize? IF not is there any other function to do this.

Thanks in advance..
priby