catchthis....They did not goof this year. If you follow their rules (which is different than the methodology of the modern Jewish calendar, which inserts Adar II at regular intervals), the date you arrive at for the beginning of Nisan 14 is 24 March 2005. Here's another way of getting to that date. The Memorial in 2004 was held on 4 April 2004. That year the spring equinox fell on 20 March 2004 and the new moon nearest to the equinox fell the very next day on 21 March 2005. Fourteen days later, Nisan 14 fell on 4 April 2005. Having established that, we can count the months of the year until the next Nisan for 2005:
Nisan 1 = 22 March
Iyar 1 = 20 April
Sivan 1 = 20 May
Tammuz 1 = 18 June
Av 1 = 18 July
Elul 1 = 17 August
Tishrei 1 = 15 September
Cheshvan 1 = 15 October
Kislev 1 = 13 November
Tevet 1 = 13 December
Sh'vat 1 = 11 January
Adar 1 = 10 February
This would place the end of Adar on 10 March 2005. Now, we could insert an intercalanary Adar II at this point; the modern Jewish calendar does this at fixed leap years, the Society does this if the next full moon after Adar 14 falls before the spring equinox. In 2005, Adar 14 falls on 25 March and the next full moon is on 25 March 2005 -- definitely after the spring equinox which fell on 20 March. Thus, Adar II is not inserted and Nisan 1 begins in March -- not April.
This year's memorial is thus consistent with their general methodology.