in British slang it means intoxicated; in Australian slang it means askew (according to our friends at OED).

"But o' course he was blind squiffy when he wrote the paper. I hope you explained that?" said Stalky. -Kipling

"I never associated it with an orgy, a term I felt to imply a Roman profusion of grapes, wine, buttocks, breasts, marble chaises-longues, and squiffy laurel crowns." -G. Melly Rum, Bum & Concertina

http://wordsmith.org/board/showthreaded.pl?Cat=&Board=wordplay&Number=25588