Quote from Bigmak:
HAHAHA...no no...I was just saying that I don't get the point of having time limits.
Because you're buying/selling a physical commodity - supply and demand effect the individual months as well as the overall product (for example winter months effect heat oil demand, or maybe you're bullish to 2007 future growth in china which requires galvanised steel which in turn effects the price of zinc so maybe you want to buy dec07 zinc rather than the typical 3 months forward price, and so on)
For the average individual commodity trading is generally expensive in margin to equity requirements (nearby crude for example is $3850 per lot in initial margins alone) so I would suggest something like SG warrants for you - go to www.sgwarrants.com - these trade just like options. I think SG let you can trade a dummy account to get a feel for it also.
Good luck