To use dynamic Internet links to connect your GroupWise system with another GroupWise system, both GroupWise systems must have at least one domain that is running one of the following versions of the GroupWise MTA:
GroupWise 5.5
GroupWise 5.5 Enhancement Pack
GroupWise 6.x
GroupWise 7
GroupWise 8
Versions of the MTA prior to version 5.5 do not support dynamic Internet links.