That is what I thought when I read this. But that really stinks that the progress has come to a halt because the coders are away.
I have really good idea right now. You probably have already considered this, but you could make certain Pokemon (or Pixelmon, whatever you'd like to call them) appear in certain biomes or areas.
\/Please read the Spoiler, it shows the areas where the Pokemon should go. Please.\/
Flying types- above level 100
Rock type/Dark types- below level 50
Ice types- winter biomes
Water types- around levels 56-72 near water (or on any level with water somewhere nearby)
Grass types/Bug types- plain and forest biomes
Ground types- desert biomes
Ghost types- only below level 16, with a rare spawn like slimes
Psychic types- similar to ghosts but maybe a little higher level/more spawn rate
Missingno.- Super-Ultra-Deluxe rarity, make it somewhere near 0.05% chance of any mob (in any area/biome) spawning being a Missingno.
If you put in missingno., you may as well do the rest of the glitch pokemon, too. Besides, the texture of missingno. is a complete piece of ****. Have you ever even seen it? Here you go.
Anyway, if you want them to add a glitch pokemon, at least have them make it ??????????.