St. Etienne striker Batefimbi Gomis was the hero in Grenoble with a second-half double for the French victory.
In Kaiserslautern, Germany led 2-0 from Miroslav Klose and an own goal from Vladimir Koryko. But Belarus fought back, exposing German defensive problems in a second-half double by Vitali Bulyga.
Two of Germany's group opponents at the June 7-29 Euro Cup, Poland and co-hosts Austria, were also in action on the night, with Austria held 1-1 by Nigeria and Poland edging Albania 1-0.
The Czech Republic defeated Lithuania 2-0 in another game.
German coach promises improvement
"All players will be in better form in 12 days time. That's a promise," said German coach Joachim Loew after the draw with Belarus.
"The players were tired after hard training. But it was disappointing that we lost a 2-0 lead."
Christoph Metzelder and Torsten Frings returned from long injury layoffs, teenager Marko Marin won his maiden cap in the second half and captain Michael Ballack played just one half for the three-time champion Germany.
The hosts got off to a strong start and took the lead when Lukas Podolski threaded a pass to his Bayern Munich teammate Klose, who rounded goalkeeper Vasili Khomutovsky and slotted into the empty net.
Germany were then 2-0 up as Koryko clumsily deflected a cross from Real Betis winger David Odonkor into his own net in the 20th.
Belarus scored in the 61st when Bulyga took up a defense-splitting pass and beat Lehmann for the first time in 681 minutes. Lehmann did not look good when the Vladivostok striker also grabbed the equalizer from long range with three minutes left.
French win, Czech faux pas
France coach Raymond Demenech rested some stars including Thierry Henry and Franck Ribery against Ecuador and the team was jeered after a goalless first half.
The hosts improved after the break and Gomis reconciled the fans with a superb effort from the edge of the area in the 59th and wrapped up matters in the 86th.
Austria, who have won just once since the autumn of 2006, led from Roman Kienast's 12th-minute shot from the edge of the area. But Nigeria levelled just seven minutes later from Kalu Uche in Graz.
Poland defeated Albania in Reutlingen, Germany, from a third-minute winner by captain Maciej Zurawski as its Dutch coach Leo Beenhakker fielded many likely Euro starters the day after experimenting in a 1-1 draw against Macedonia.
Poland dominated and were unlucky when defender Mariusz Lewandowski was denied by the post in the 48th.
The Czechs, due to play the Euro opener on June 7 against co-hosts Switzerland, beat Lithuania with veteran Jan Koller's double in 39th and 62nd minutes.
The victory was partly spoiled by an embarrassing blunder on the part of the Czech Football Association, which had confused Lithuania with another Baltic state, neighboring Latvia. A Latvian flag and the photo of the Latvian team were depicted in the official brochure and the Latvian anthem was played ahead of the match.