Stocks were on the retreat after the closing bell Monday following the regular session's slight recovery, and contributing to this trend were several tech names.

Shares of

Openwave Systems

( OPWV), a software developer for the communications and media industries, plunged 13.2% in heavy trading on word it has been

unable to find a buyer

. Its board, moreover, rejected last month's $8.30-a-share cash offer for around 49% of the company by big shareholder Harbinger Capital. California-based Openwave was losing $1.37 to $8.99.

Communications-equipment maker


(CIEN) - Get Report

fell 3% to $33.81 after saying it will

sell up to $450 million in convertible senior notes

, as well as an underwriters' option for another $50 million worth to cover any overallotments.

Also losing ground was

Credence Systems

( CMOS), which makes test and diagnostic systems for semiconductor production. The Milpitas, Calif., company posted a fiscal second-quarter loss of 3 cents a share, which, despite narrowing significantly from last year, falls short of analysts' break-even expectations, per Thomson Financial. Shares gave up 1.2% to $3.39 in recent after-hours trading.

Oil-and-gas driller

XTO Energy

( XTO), based in Fort Worth, Texas, slipped 0.8% to $61.11 after saying it will offer 15 million of its shares under an existing shelf registration, along with a 2.25-million-share underwriters' option.

Among the winners, meanwhile, was

Mitcham Industries

(MIND) - Get Report

. The Huntsville, Texas, company, which leases and sells equipment to the seismic industry, said per-share income rose by 6 cents year over year to 39 cents, or $3.9 million, in the quarter ended April 30. Revenue leapt 63% to $23 million. Shares lately gained 63 cents, or 3.5%, to $18.70.