Lanefan
Victoria Rules
Which is, in true 1e fashion, why the MU brings along a meat-shield henchman; to guard against exactly this.A longsword equivalent will incapacitate the max-hp Magic-User more than 50% of the time -- assuming no strength bonus or additional damage (and death will occur 1 in 8 times even if the optional -3 rule is in play). That assumes no Con bonus. Though even with a 16 or better Con, the Magic-User will become incapacitated over 1/3 of the time from a single hit.

If it gets to the point where your MU is within reach of someone's longsword, something's gone rather wrong either with your stealth, your tactics, or your surprise rolling...
Lan-"that said, I do own a longsword +2, wizardslayer"-efan