It occurs with Hudson ver. 1.393-SNAPSHOT (private-01/01/2011 21:34-olamy) but probably also with latest 1.392
The test case is simple.
A project with a parent like this :
And in the module subdir/mod1
Not that there is no module in subdir and mod1 doesn't say where to find its parent with a relative path.
Such a build passes with M2 and fails with m3 with an error like :
The issue with using m3 to parse m2 projects is that some builds that passed previously (because it was allowed by m2) doesn't work anymore.
I attach a testcase