Can the 3rd-level Clr spell glyph of warding [abjur] (PH 237-8) et al. be cast on ammunition (perhaps necessitating something like the prestige class arcane archer's special ability imbue arrow) or on a melee weapon so that when it hits a foe a spell glyph triggers or a blast glyph explodes?
Note: In comments on this answer, it was suggested that the special ability imbue arrow be combined with the spell glyph of warding to make arrows have spell or blast effects upon hitting their targets. I put forth that the target of such an arrow wasn't trying to enter, open, or pass the arrow so the glyph didn't seem to matter. This question attempts to resolve this issue rather than continue the conversation in comments.
Best Answer
For my money/at my table:
Casting the spell on an object does not work.
The Glyph of Warding spell can be cast on either an object or an area. For the object version, only "opening the warded object" is mentioned as a valid trigger. As the question points out, being hit by an arrow or a sword is definitely not the same thing as trying to open an object (heck, the object is trying to open you)!
The area version is less clear, but I think it works at least somewhat.
The Arcane Archer's Imbue Arrow ability, fortunately for would be Glyph-cheese-practitioners, isn't using the object-targeting version of the spell. As a matter of fact, the ability specifically requires that it be used with an area spell, and then casts that spell with its area centered wherever the arrow lands.
Here's the relevant text concerning what can trigger a Glyph:
I see two possible interpretations here:
I favor the first interpretation here, because "you set the conditions of the ward" reads like a blanket statement to me, and because it's less clunky to use, but I could definitely see a DM going either way on this.