I have a Blackberry 8900 and use the subscription from MTN for which I pay =N=5,000 per month (prepaid).

When I first got the BB, I asked MTN if I would be able to watch streaming videos like youtube and things like that under the subscription. They assured me that I could do this. So imagine my surprise when I went online with my BB and watched a 3-min video and got charged =N=1,200 for that!!  (my balance on *556# reduced by 1,200)

Does anyone know how many Mb of downloads the subscription offers? And how do I know if any sites I visit online thru my BB will charge me from my normal balance?
Thanks