I understand that you can't post proprietary code. Can you you reproduce the problem with a simple pom.xml that you can share?
Also, does the same problem show up with Eclipse Indigo (3.7) and Maven 3.0.3?
At this point I am assuming an incompatibility between your POM and the Maven built into Eclipse Helios. (Which is the reason I rarely let Eclipse build anything...)
Finally, have you tried doing the build within Eclipse using the -X option - that might give more clues as to the problem.