Minor Description
This works for me:
<wicket:message key="key">bla</wicket:message
This causes an infinite loop:
<wicket:message key="key">bla <a href="bla">bla</a> bla</wicket:message>
Generally I don't use markup in a wicket:message but I just copy pasted this for mockup purposes; I think it should work, but it definately shouldn't go into an infinite loop.