[Koha] Search engine configuration error

[Araik Manukyan]

Hi list.
We have 3 servers of Koha (3.10,3.12, 3.12.01) on Ubuntu  12.04
We have some problem (on the 3 servers) when clicking Search engine
configuration in System preferences.It brings such error :
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Software error:
 
`Koha::SearchEngine::::Config' is not a module name
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Any suggestions?
Araik.