In the first 15 minutes of trading, the 225-issue Nikkei Stock Average gained 2.19 points, or 0.02 percent, from Tuesday to 10,569.84. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was up 0.49 points, or 0.05 percent, to 924.87. The Second Section also advanced.

Gainers were led by the miscellaneous sector -- which includes printing companies and games giant Nintendo -- followed by the electrical machinery sector and the insurance sector. Major decliners included oil and coal product, sea transport, and iron and steel issues.

Although the key indexes moved in positive territory, gains were capped by investors' reluctance to seek higher ground amid a lack of new trading incentives. Gains by Wall Street were too modest to stoke Tokyo buying, brokers said.

Currency movements also discouraged investors from taking bold positions, they said.

The dollar was trading Wednesday morning around the 90 yen line in Tokyo, up slightly from the 89 yen zone late Tuesday in local trading, though it may again loose upward momentum later in the day, brokers said. A stronger yen versus the dollar erodes the profits of Japanese exporters when repatriated.