1993: Janet Reno issues a legal opinion that the president can issue a recess appointment when congress adjourns for three days or more.
1999: President Clinton uses a recess appointment to appoint James Hormel as ambassador to Luxembourg, as his appointment had been bottled up by conservative Republicans, opposed to him due to his homosexuality. Ted Kennedy was one of his chief supporters. The appontment occurs during a 10 day recess which includes Memorial Day.
2004: President Bush uses a recess appointment to appoint William Pryor to the 11th Circuit Court of Appeals, after Democrats filibustered his nomination (because they did not have enough votes to defeat him).
Edward Kennedy issues a vindictive, nasty press release which libels Pryor and Bush. He then asks the 11th circuit to consider whether the appointment is unconstitutional, due to the short length of the recess. It's part of what appears to be a coordinated media campaign, since other charges are flying, all issued from Kennedy's office.
I didn't hear Kennedy screaming over the Hormel and Bill Lann Lee appointments. Of course, they pass his ideological litmus test. Pryor apparently, fails, although I wonder if Kennedy considers his prosecution of Roy Moore to be characteristic of a nominee who possesses "... questionable commitment to the authority of the Supreme Court and the rule of law." Somehow, I don't think so.