Reliance Money Interest Charges

I have my trading account with reliance money and I found the following message on the website :

"Please note that interest will be charged on trade-related debits in your account. This includes debit balance on delivery transactions and debits against mark to market on Futures and Options segment.
For Limit Card clients, interest charge would be applicable from 1st of January, 2010.

Interest will be chargeable at the end of day T in case of debits and will cease on the T day in case debits are settled by trading credits or credits from sale of shares.

The interest rate chargeable, are as follows:
Limit Card Clients At the rate of 21% per annum.
Percentage Brokerage Clients At the rate of 18% per annum. "


Can someone explain me what are these trade related debits.

Thanks in advance.

sir
int charge by rel money of 21% is high
and trade related debit means intraday and delivery transaction on delivery transaction
a delivery charge of rs 25 maximum is charge i.e minimum is rs 15 add srtax

Can you please explain this in brief. Will this phrase means "interest applies even on existing shares" in the demat account or is it applicable to the new transactions after jan'10.
Which is better limit card or percentage brokerage?

Thanks in Advance.