Bothell-based Dexterra, a mobile software company that has raised $106.5 million since its founding in 2002, including a $21.5 million round last fall, is nearing a sale. Two knowledgeable sources identified New Jersey-based rival Antenna Software as the potential buyer.

We've been unable to get confirmation from the companies. A spokesman for Antenna said today: "I'll have to get back to you" and then later declined to comment. Calls and emails to Dexterra were not returned. We're hearing that the purchase price was in the range of $18 million, but that hasn't been confirmed, either.

One source had not heard the $18 million figure, but noted that "no one is making money off of this deal."

The deal is expected to close as early as today. Both sources said that Dexterra entertained at least one other offer.

Dexterra's software helps workers in the field access corporate information from mobile devices. Founded by Rob Loughan, the company tapped former IBM executive Michael Liebow as CEO last summer. The company -- which employed 145 people as of last fall -- is backed by New Enterprise Associates, Canaan Partners, Intel Capital, Mesirow Financial, Motorola and Sigma Partners.

But the company hit hard times, losing its sales force and key contracts, sources say. Over the past few months, dozens of employees have been laid off, with one source saying about 40 people now work at the company.

At the time of the funding last fall, NEA's Scott Sandell said that Dexterra was in a good position.

"Today's challenging economic environment makes deciding which companies to invest in more difficult than ever," Sandell said in a statement at the time. "We've been closely watching the growth of enterprise mobility and Dexterra is well positioned as a market leader."

Sandell could not be reached today.

UPDATE: Antenna confirmed the sale on Monday. Here's the latest report.