Habe nochmal nachgefragt und von einem (nicht-offiziellen) Regelguru folgendes erhalten:
Considerations for range are made from the square(s) the character occupies, not the square(s) they can reach into. For example (from Player's Handbook on page 152):
Quote:To determine whether your target has concealment from your ranged attack, choose a corner of your square. If any line from this corner to any corner of the target’s square passes through a square or border that provides concealment, the target has concealment.
The diagram explaining cover vs. ranged attacks on page 151 shows that the character's reach doesn't matter, because if it did Lidda's 5' reach would allow her to pick an adjacent square's corner and avoid cover penalties against the Orc. Also, the rules don't have you subtract your natural reach from the range before determining range penalties when you throw a projectile; there's no distinction between range for projectile weapons and range for thrown weapons (see Rules Compendium on page 16).
And, since we're specifically talking about the range for spells, there's this (from Player's Handbook pages 174-175):
Quote:RANGE
A spell’s range indicates how far from you it can reach, as defined in the Range entry of the spell description. A spell’s range is the maximum distance from you that the spell’s effect can occur, as well as the maximum distance at which you can designate the spell’s point of origin. If any portion of the spell’s area would extend beyond this range, that area is wasted.
All positional references to "you" in the rules refer to the squares you occupy, and not the squares you can reach into. Enemies can only attack you in those spaces you occupy, and can't attack your arms when they reach out of your square(s).
Rules Compendium phrases this slightly differently on page 126:
Quote:RANGE
A spell’s range is the maximum distance from you at which the spell’s effect can occur ...
TOUCH
You must touch the target to affect it. Some touch spells allow you to touch multiple targets. If you aren’t in combat when you cast a touch spell, you can touch as many willing targets as you can reach as part of the casting.
As given in the rules, the range of a touch spell varies with the caster's natural reach; it's not fixed.
tl;dr: "No, because it varies with the caster's reach."