forum game of what type? roleplaying?
maybe it's more of a subjective problem. there are different ways of roleplaying (i have been and am a dungeon master, a vampiric Narrator and so on for a long long time) and i have seen around the net that each forum has it's own way of roleplaying.
usually they are the "One dm, the rest is players", "one dm who also is the player, the rest is players", "no dm OR everyone dm" (usually in the bay12 forums, where you can do what you want, as long as it doesn't ruin another ones game, or is not so strange and bizzare to be unintelligible. ( man did i spell that right?) )
in any case yeah, usually 99% of roleplaying problems can be solved through speaking, and chatting in a normal and sincere way.
most probably, seeing how he only writes about generic actions and vague postings, either he is new altogether to the RP thing (which may be, as this would mean he is just testing the waters) or he simply is given in the real life a dungeon master who solves the problems for him (and the group he might be in).
For dungeon master, while it might be a d&d term, i'm referring idealistically to any sort of master/narrator/chief overseer computer/ excetera.
that said, wait and see, then wait and hear him out, then if it persists go and search or try and do without. games are fun when people aren't obliged to play them. and in RPs strangely sometime someone gets the idea he MUST post as if it were an order. He should post because it's fun, not because he is ordered to do so or because he thinks it's like the dentist, you don't like it, but have to go...
you shouldn't give offers. you should clearly state to him that he should be mature enough to understand that playing in a determinated way will only yield determinate results.
i had a similar case. he would post once every death of a pope, would do nothing but right "i wait" or "i follow" and then when asked the why he would bicker that he would was left behind in the Rp. And once you made him note that it was his fault, he would simply log off with a "whatever" for a couple of weeks. then come back with a "i'm sorry, i was stressed for work/school/family matters/university" the like.
then i found out he was actually playing on an italian world of warcraft shard.
the blood is still hard to remove from the keyboard they tell me.