Kozmo.com

, the Internet-based delivery service, said its CEO would hand over his duties to the current CFO, a sign the money-losing company is attempting to gain more credibility with investors as it prepares for its initial public offering.

Joseph Park will step aside as CEO, though he'll remain chairman. He'll be replaced by Gerry Burdo, the former principal financial officer of

Ethan Allen

(ETH) - Get Report

who joined Kozmo.com as CFO in November.

Kozmo.com is one of a handful of so-called last-mile Internet companies offering speedy delivery of goods ranging from the latest Harry Potter book to a bag of Jelly Bellies within an hour or so of ordering. Other competitors in this area include

Urbanfetch

and

Webvan

(WBVN)

. However, there are plenty of doubts about whether these companies can ever make money, given the big capital investment necessary and relatively small average order size.

Kozmo filed to go public earlier this year, but postponed its IPO due to poor market conditions for Internet stocks.