you're right. He was asked about Obama's qualifications, but instead of addressing Obama's experience and abilities, he gave the Constitutional answer.
And instead of phrasing the answer like "Obama is qualified under the Constitution...", he said "The Constitution defines who is qualified...", which leaves open the possibility that Obama may not qualify.
The Clinton's choose their words extremely carefully. As weird as this seems, the Clintons may be expecting this issue to explode.
The standard for President was the highest.......And probably intended that BOTH parents were Loyal Americans and Citizens at the time.