can't make custos engraver work properly

[Wasil Sergejczyk]

errors are the following:

programming error: No spacing entry from KeySignature to `custos'
continuing, cross fingers
programming error: No spacing entry from KeyCancellation to `custos'
continuing, cross fingers

here is the file:

http://pastebin.com/x6K9eJPK

lilypond version 2.15.40 (compiled from git official branch source), operating system Ubuntu Linux oneiric.

i've found something from this maillist, but it's from 2003 and doesn't seem to work now.

please, help. thanks in advance.

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Best regards.