Edit field problem in IWP.

When I make edit fields in filemaker, in the field behavior I always set to go to the next field via tab, enter, or return. Of course, in IWP only tab works. My question is this:

is there a way to prevent edit fields from dropping down to a new line when the enter key is pressed? It looks to me as if, when filemaker generates the web site, it uses "text areas" for all of the edit fields instead of "text fields" (those are html form terms). So basically, all of the edit fields become multi-line fields in IWP and pressing the enter key drops down to a new line. Is there a way to set up IWP somehow so that text fields will be created instead of text areas? I don't want the user to be able to submit multi-line data.