Odd unable to delete msgs in log on 2.5.2 upgrade

I'm not sure if this is affecting anything but during a test upgrade from 2.3 to 2.5.2 I see the following in stdout:

Deleting C:\jira\atlassian-jira-professional-2.5.2-standalone-tomcat\bin\alt.java.io.FileImpl@1198a2;comments
message = Unable to delete file C:\jira\atlassian-jira-professional-2.5.2-standalone-tomcat\bin\alt.java.io.FileImpl@1198a2;comments
Deleting C:\jira\atlassian-jira-professional-2.5.2-standalone-tomcat\bin\alt.java.io.FileImpl@1198a2;issues
message = Unable to delete file C:\jira\atlassian-jira-professional-2.5.2-standalone-tomcat\bin\alt.java.io.FileImpl@1198a2;issues

Seemed funny to see the file object's toString being spat out - could just be how it's logging.

My import file contains a few D:\ directories (from the server I actually run the app on), but I'm testing on a PC with just a C:\. Usually no problem upgrading, but a few "missing backup dir" and such errors that I expect.