For the Biblio Transformation Engine (BTE), DSpace includes dependencies on 'bte-io' and 'bte-core' versions 0.9.2.3 in it's main POM:
Unfortunately, it seems that 'bte-core' version 0.9.2.3 itself has a dependency on 'bte-core' version 0.9.2.3-SNAPSHOT in its POM in Maven Central:
Since the 0.9.2.3-SNAPSHOT version of 'bte-core' doesn't seem to exist in Maven Central (or in Sonatype's Maven repo), we are now seeing the following WARNING when building 'dspace-api':
"[WARNING] The POM for gr.ekt.bte:bte-core:jar:0.9.2.3-SNAPSHOT is missing, no dependency information available"
It looks like this 0.9.2.3-SNAPSHOT version is not available anywhere publicly.
This POM problem is really just a WARNING reported by Maven. DSpace 4.x will still build properly with this missing dependency.