Re-indexing shows error: java.lang.NumberFormatException: For input string: ""

When trying to re-index a workspace/folder in Vibe, the re-index process report one or more errors encountered. Reviewing the Vibe server's catalina / appserver log file reveals the following errors:

2015-05-13 13:20:10,640 ERROR [TP-Processor777] [org.kablink.teaming.module.folder.impl.DefaultFolderCoreProcessor] - Error indexing entry: (651869) my entry
java.lang.NumberFormatException: For input string: ""
    at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
    at java.lang.Long.parseLong(Long.java:431)
    at java.lang.Long.valueOf(Long.java:525)
    at org.kablink.teaming.module.definition.index.FieldBuilderUserlist.build(FieldBuilderUserlist.java:53)
    at org.kablink.teaming.module.definition.index.AbstractFieldBuilder.buildField(AbstractFieldBuilder.java:66)
    ....

A fix for this issue is available in the Vibe 3.4 Hot Patch 2 / Vibe 4.0 Hot Patch 1, available via the Novell Patch Finder.