In the US (english language) Bastard is...
bas·tardnoun
1. A child born out of wedlock.
2. Something that is of irregular, inferior, or dubious origin.
3. Slang. A person, especially one who is held to be mean or disagreeable. [/i]
adjective
1. Born of unwed parents; illegitimate.
2. Not genuine; spurious: a bastard style of architecture.
3. Resembling a known kind or species but not truly such.
I would guess that you were using the term as a noun in definition number 3 (
italics). In this case, your use of the term is technically correct, as in the actions of the person who rammed you were disagreeable, at least to you.
It is possible that the moderator, in his infinite and all knowing wisdom

was assuming that you were using the term in definition 1, which would be derogatory towards the other player in that you have no idea if he was born out of wedlock, thus making your statement inflamatory and uncalled for.
I cases like this, it would have been better for the moderator to ask you to refrain from such language in the future and take into consideration the multi-cultural diversity that is Aces High. There needs to be a greater latitude in what people say and how certain terms may be inturpreted by others.