The most recent episode of the Sacred Page podcast features New Testament scholar Brant Pitre (rhymes with "B-tree," not "fighter") defending the interpretation that the Last Supper was indeed a Passover seder.
In case you're not familiar with the issue here, there is an apparent contradiction between the synoptic gospels, which describe the last supper as a Passover seder, and John's gospel, which contains several statements appearing to suggest that Passover night happened AFTER Yeshua's crucifixion.
A number of theories have been proposed to resolve this difficulty: two of the most popular are (1) that Yeshua celebrated an "anticipatory Passover meal" with his disciples and (2) that Yeshua celebrated on Tuesday night in accordance with the Essene calendar, a solar calendar whose existence and usage in the Second Temple period is attested to by the book of Jubilees.
In contrast to these theories, Brant Pitre asserts that the word Pascha/pesach is actually used in four different ways in Second Temple texts, and that it is ignorance of these possible meanings or to the surrounding context which implies one meaning or another that has caused scholars to confuse John's usages of the word pascha,creating the appearance of a contradiction.
Check it out at the Sacred Page podcast: Brant Pitre on the Date of the Last Supper
Oh, and chag sameach, everybody.