Do you know spam
when you see it?

A new report by Dot Email finds email marketers believe AOL's mail service to be the biggest hassle in terms of deliverability, while Gmail is the easiest.

Some 38.4 percent said AOL has the lowest deliverability of marketing messages, while only 7.1 percent think Google's Gmail had the lowest, according to DM News.

MSN/Hotmail came in second with 21.4 percent, followed by Earthlink with 17 percent and Yahoo with 16 percent.

Gmail may have a firmer handle on keeping marketing messages out of the spam folder, thanks to its recent purchase of Postini, the largest filtering company.

But Gmail also has the lowest market penetration against heavyweights like AOL or Hotmail, which were sending mail well before the dot-com bust.