There are two revisions of 2003 MDD's. There are Januarys and Junes. The Januarys could not boot OS 9, the Junes could. Yes, it was a weird move on apple's part. They needed to get rid of parts and decided to release one last OS 9 mac. (Like how the Yikes used lots of B&W G3 parts that were left over) (Kinda funny to note: two years before the intel transition they were stilling selling OS 9 machines :lol: )
...and the Apple Power Macintosh G4 1.25 DP (MDD), intro'd June 23, 2003 and produced until June 9, 2004 . They are literally the same. The bus speed is only different if you had an 867MHz Dual MDD 2002. (The 867's having a 133 bus. The others having 167MHz.)