currency conversion

Hi experts,

Can anybody give me the Function Module name to convert one currency into another currency with the mandatory parameters. I used a Function module HR_ECM_CONVERT_CURRENCY to convert amount from EUR to DEM but if i give 1, the amount in DEM comes as 0. if i give 1.0, then it returns, 2. and for 1.00, it returns 20. So for a same number with different decimal places, it returns a dfferent amount. What is the actual conversion taking place here. Using which FM will provide the correct conversion.

Thanks in advance,

Shanthi.