It is a bit strange question. Do you already use webmoney?
Then you must know that:
1) WebMoney has its own BTC to WMZ exchange system and rates
2) Webmoney has its users' market where you can make deals (even better rates than WebMoney's defalt rates)
You can have WMX wallet with Bitcoins and you can send them anywhere. The process may take a bit longer than in other exchanges - doe to security reasons they moderate sending request and then make 120 confirmations for sending.