The data sheet for IBM Sterling B2B Integrator fo EDI mentions support for many business protocols, including ebXML as well as for the EDIINT protocols AS1, AS2, AS3 and AS4. AS4 is the B2B Web Services profile based on ebXML Messaging Version 3.0.
The AS4 specification is available for download from http://docs.oasis-open.org/ebxml-msg/ebms/v3.0/profiles/200707/. One updated version will be posted there shortly, with another update in the next few weeks. and the OASIS ebMS TC intends to progress this specification to OASIS Standard level later this year.
The Sterling product already supports the older version 2.0 OASIS ebXML Messaging standard, and many other protocols.