Fixed a bug that made crash the solver for some constraints.

1 job for master in 18 seconds (queued for 26 seconds)
Status Name Job ID Coverage
  Build
failed mybuild #370

00:00:18

 
Name Stage Failure
failed
mybuild Build There is an unknown failure, please try again
	at org.eclipse.aether.connector.basic.BasicRepositoryConnector$GetTaskRunner.runTask(BasicRepositoryConnector.java:447)
at org.eclipse.aether.connector.basic.BasicRepositoryConnector$TaskRunner.run(BasicRepositoryConnector.java:350)
... 32 more
7016 [ERROR]
7017 [ERROR] Re-run Maven using the -X switch to enable full debug logging.
7017 [ERROR]
7017 [ERROR] For more information about the errors and possible solutions, please read the following articles:
7017 [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
ERROR: Job failed: exit code 1