What does "at least one <locale> entry in a <schema>" mean?

Today the update-manager installed
pool/main/d/deskbar-applet/deskbar-applet_2.20.0-0ubuntu2_i386.deb
on my Computer running Ubuntu 7.10 (Gutsy).

During this step the following warning message was displayed:
"You must have at least one <locale> entry in a <schema>"

Since a simple Google search using this phrase offered only 9 results
and none of these answered my question, I ask here:
What does this message mean?

I don't know if this matters:
I use the German locale, because this is my native language.
My machine was originally installed with Ubuntu 6.10 last year
and than upgraded to 7.04 and 7.10 in turn.

Thanks in advance and best regards, Peter