From the Vatican Information Service:
The first question is: "Is a Baptism valid if conferred with the words 'I baptise you in the name of the Creator, and of the Redeemer, and of the Sanctifier', or 'I baptise you in the name of the Creator, and of the Liberator, and of the Sustainer'"?
The second question is: "Must people baptised with those formulae be baptised 'in forma absoluta'?"
The responses are: "To the first question, negative; to the second question, affirmative".
Fortunately, the stupidity of using "creative" baptismal forms isn't as prevalent today as it was in the 80's and early '90s. Back then, it seemed like every wifty, self-styled "hip" priest was coming up with his own baptismal formula, marked by his own oh-so-personal style. Never mind the Lord's specific command and the universal practice of the Church for 20 centuries...
Back when I was in graduate school at Catholic University (early-mid '90's), such a baptism took place on campus. It was not conducted by a university chaplain, but by an outside priest for an alumnus in one of the University chapels. The story got out and created a bit of a stir: the Archdiocese of Washington apparently got involved and insisted the child be re-baptized using the proper formula. Why? The response of the CDF explains:
"Variations to the baptismal formula - using non-biblical designations of the Divine Persons - as considered in this reply, arise from so-called feminist theology", being an attempt "to avoid using the words Father and Son which are held to be chauvinistic, substituting them with other names. Such variants, however, undermine faith in the Trinity".Let's hope this declaration puts an end to such nonsense once and for all.
"The response of the Congregation for the Doctrine of the Faith constitutes an authentic doctrinal declaration, which has wide-ranging canonical and pastoral effects. Indeed, the reply implicitly affirms that people who have been baptised, or who will in the future be baptised, with the formulae in question have, in reality, not been baptised. Hence, they must them be treated for all canonical and pastoral purposes with the same juridical criteria as people whom the Code of Canon Law places in the general category of 'non-baptised'". (my emphasis)