Please do not lock Jobs to the Weapon Class that unlocks them.

[Lerris]

Not to mention the letter X clearly says introduction of Job specific weapons and gear.

Job specific weapons and gear does not necessarily imply additional weapon types.

Assuming thief, red mage and paladin are all usable with gladiator:

Joyeuse could be red mage specific
Excalibur could be paladin specific
Hornetneedle could be thief specific.

All job-specific weapons keyed to a single existing class. A speculative scenario which works just as well regardless of whether jobs end up locked to particular classes or not.