Modification sent to the server while browsing through the DIT and refreshing entries

I walk throught the DIT using mouse and/or arrow keys and refresh entries from time to time. Suddenly an error dialog pops up, an modification request was sent to the server!

#!RESULT ERROR
#!CONNECTION ldap://localhost:10389
#!DATE 2009-11-19T21:09:51.497
#!ERROR [LDAP: error code 65 - OBJECT_CLASS_VIOLATION: failed for Modify Request Object : '0.9.2342.19200300.100.1.25=example,0.9.2342.19200300.100.1.25=com' Modification[0] Operation : delete Modification objectClass: (null) : null]
dn: dc=example,dc=com
changetype: modify
delete: objectClass
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