The Justice Department has asked for additional information for an antitrust inquiry on IBM Corp.'s proposed $1.25 billion takeover of Rolm Corp., the two companies said yesterday.

They said they would comply with the request as soon as possible. Rolm, a Santa Clara, Calif.-based telecommunciations-equipment firm, still plans to proceed with a shareholders meeting it has scheduled for Nov. 21 to vote on the proposed deal, even though the Hart-Scott-Rodino Antitrust Act stipulates that an acquisition cannot be completed until 20 days after the submission of any additional information requested by the Justice Department.

The companies said they will ask for early termination of the 20-day waiting period, which can be granted by the Justice Department.

The information requested by the Justice Department concerns the companies' involvement in the military computer business, IBM and Rolm said. The companies reiterated earlier statements that they do not believe their merger violates antitrust laws. They added that they expect to consummate the deal soon.

The Justice Department has been conducting a routine antitrust inquiry into the proposed merger since IBM announced plans in late September to purchase the 77 percent of Rolm it did not already own.

Analysts saw the merger as a way for IBM to make up ground in the field of telecommunciations equipment. IBM already is laying plans to combine its technology with Rolm's to create a new line of products that package personal computers with office telephones.