IP issue resolution for XML Signatures

Is there any projected date to know how encumbered XML Signatures will be to previous IP?  There are comments about a few patents, but is there a process to determine if there's infringement, and if so, what the royalty requirements will be?

A standard that's encumbered by IP issues will surely fail to be adopted widely, so it's important to know when it really makes sense to use XML Signatures in an application.  We'd hate to adopt this and then suffer similar issues that surrounded WAP/WML when one party may require royalties and the like to use an "open" protocol.

Thanks,
David