Looking at page like http://deadlock.netbeans.org/hudson/job/trunk/7635/changes, there is a whitespace at the end of the user name "Alex Petrov " in this case.
I can't spot if this is caused by the core or by the plugin, but such whitespace should be trimmed.
|Field||Original Value||New Value|
|Assignee||Kohsuke Kawaguchi [ kohsuke ]||Jesse Glick [ jglick ]|
|Status||Open [ 1 ]||In Progress [ 3 ]|
|Status||In Progress [ 3 ]||Resolved [ 5 ]|
|Resolution||Fixed [ 1 ]|
|Workflow||JNJira [ 135541 ]||JNJira + In-Review [ 186993 ]|