For artifact {org.jvnet.staxex:stax-ex:null:jar}: The version cannot be empty.

All,

I am running eclipse:eclipse on a project and getting the

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-eclipse-plugin:2.9:eclipse (default-cli) on project installer: Execution default-cli of goal org.apache.maven.plugins:maven-eclipse-plugin:2.9:eclipse failed: For artifact {org.jvnet.staxex:stax-ex:null:jar}: The version cannot be empty. -> [Help 1]

After some debugging, I notice the following warning

[WARNING] Invalid POM for com.sun.xml.stream.buffer:streambuffer:jar:0.4, transitive dependencies (if any) will not be available, enable debug logging for more details: Some problems were encountered while processing the POMs:
[ERROR] 'dependencies.dependency.version' for org.jvnet.staxex:stax-ex:jar is missing. @ line 7, column 17
[ERROR] 'dependencies.dependency.version' for activation:activation:jar is missing. @ line 11, column 17

I pulled up the pom file for com.sun.xml.stream.buffer:streambuffer:jar:0.4, and it is in-fact missing versions for its dependancies.
I figured I would include a newer version of streambuffer.jar in my pom explicitly (which has correct pom) but for some reason, maven is still choosing the transitive version of the dependency over my explicitly declared one.
Removing it:
com.sun.xml.stream.buffer:streambuffer:jar:0.7:compile (removed - nearer found: 0.4)

This project is a child project of another project.

TWO QUESTIONS:

In what cases will maven choose a transitive dependency version over an explicitly declared one in the pom?
Is there a way to make maven less sensitive - to missing versions in poms?

I am currently running:
Apache Maven 3.0.5 (r01de14724cdef164cd33c7c8c2fe155faf9602da; 2013-02-19 13:51:28+0000)