Atlantic Telephone Membership, a North Carolina-based communications services provider, became one of the first customers of CommWorks' partnership with Copper Mountain.
The contract sent shares of Copper Mountain more than 11 percent higher to close at $5.19 Monday.
Atlantic Telephone on Monday agreed to purchase high-speed DSL (digital subscriber line) equipment from CommWorks.
Analysts and investors have feared that Copper Mountain's customer base has eroded because of tightening capital markets for its primary customers.
Many DSL wholesalers and broadband Internet providers have struggled in recent months as investment capital has become scarce and their financial reserves have dwindled.
CommWorks, a 3Com subsidiary that develops high-end gear for communications carriers, developed DSL equipment via a partnership with Copper Mountain, a DSL hardware maker. The deal is significant for Copper Mountain because the company's stock has plunged in the past year.
Atlantic Telephone, founded in 1957, offers high-speed Net access to about 40,000 customers in rural southeast North Carolina. The company added wireless services in 1996.