It means either
1) The resource killmessages has been modified and not restarted
or
2) The client is having problems downloading 'gun_dildo1.png'
If the problem is only occurring with one player, ask them to manual delete the client cache of killmessages by deleting:
C:\Program Files\MTA San Andreas 1.5\mods\deathmatch\resources\killmessages
or
C:\Program Files (x86)\MTA San Andreas 1.5\mods\deathmatch\resources\killmessages