CHICAGO, Oct 11. /Reuters/. Lumber futures at the Chicago Mercantile Exchange were sharply higher early Friday amid support from strength in the cash market, where traders said business has been continuing at a brisk pace for four days. At 9:27 a.m. CDT, lumber futures were $3.90 to $7.30 per thousand board feet higher, with November up $3.90 at $234.00 and January up $5.20 at $252.90. Traders said the early buying touched off buy stops. They said the pick up in business in the cash market was fueling expectations that cash prices would rise even higher. On Friday, Random Lengths quoted the standard and better cash spruce price at $197 per tbf, unchanged from midweek and up $4 from last week. No. 2 and better was quoted at $211 per tbf, up $1 from midweek and up $7 from last week. It said a few more sawmill curtailments were announced. While having little direct effect, they reinforced the notion that prices had little downside potential. Rumors circulated that a major producer would curtail a number of operations, but no announcement had been made by late Thursday, the reporting agency said. Reuters news service