grey matter your right because i have created servers with mods under the name baseoa and could have gone unnoticed that there was a mod present
Be sure you know what you are doing when messing with baseoa... if clients would download some kinds of stuff, they may get problems.
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DO NOT LINK) h t t p s : / / openarena . wikia . com/wiki/Faq#Yesterday_everything_worked_correctly.2C_but_today_I_experience_strange_problems
I don't know how to use serverside mods, I cannot help there.