Post 1.1 xpath functions

I am working on implementing the functions for MozzIE to make it 1.1 
compliant.  I have already found that there is a proposal for a post 1.1 
function called bind() which I have added as an extension function.  
What other post 1.1 functions are on the table?
In particular I am looking at adding an extension function called 
encrypt() that will encrypt an element/attribute using a public key.  I 
have a particular requirement to allow a form to post a fragment back to 
a server where the contents (a new password) needs to be encrypted using 
the server's public rsa key.
The footprint would be the same as the hmac() function, only the 
algorithm would be some form of encryption algorithm rather than an hmac 
and the result would be an encryption of the data.
Has this been discussed at all? If so is there a thread I can see what 
the thoughts were.

regards