-current postfix breakage? (on sparc64)

I'm having trouble with my postfix on my sparc64 machine not being able to
deliver mail after upgrading the kernel to a few-day-old 4.99.69 and then
upgrading userland to the matching build. This happens on both sparc64
boxes that I upgraded, in fact, but not on the shark or the SGI O2 (yes,
I had a upgrade party earlier this week).

ktrace says:

10993      1 smtp     CALL read(0xc,0x41350010,0x1000)
10993      1 smtp     GIO   fd 12 read 27 bytes
       "220 remote-mail-server ESMTP Postfix\r\n"
10993      1 smtp     RET   read 27/0x1b, 1093992464/0x41350010
10993      1 smtp     CALL gettimeofday(0x41336668,0)
10993      1 smtp     RET   gettimeofday 0
10993      1 smtp     CALL mmap(0,0xb6891000000,3,0x14001002,0xfffffffffffffff
f,0,0)
10993      1 smtp     RET   mmap -1 errno 12 Cannot allocate memory

and the log says:
postfix/smtp[xxx]: fatal: mymalloc: insufficient memory: Cannot allocate memory

Sounds like something's wrong with the latest postfix import.. be interesting
to know if it's endemic to all 64-bit archs, or sparc64 specific..

Thanks,
--rafal