Frauds using the name of well known companies

Dear partners,
we have some alerts about frauds using the name of well known companies. Speedflow company notify us about some swindlers trying to make conversation using the company's good name and e-mail: speedflow@live.com.
We would like to pay your attention about letters from domain name < @speedflow.com > to be the only valid letters from Speedflow Communications Ltd.
Please be carefull in situation like that and don't hesitate to call to the company and ask whether concrete e-mail address is the true address for this company.