Cisco 3640 Flash errors - upgrade bootrom?

[Kim Onnel <karim.adel () gmail com>]

I have a 3640 that while booting up gives the errors below at the console,

Console Errors:
_____________

C3600 processor with 65536 Kbytes of main memory
Main memory is configured to 64 bit mode with parity disabled

unknown flash deþ
System Bootstrap, Version 11.1(7)AX [kuong (7)AX], EARLY DEPLOYMENT RELEASE SOFT
WARE (fc2)
Copyright (c) 1994-1996 by cisco Systems, Inc.
C3600 processor with 65536 Kbytes of main memory
Main memory is configured to 64 bit mode with parity disabled

unknown flash device - mandev code = 0xffff
cannot read flash info
getdevnum warning: device "flash" has size of zero
unknown flash device - mandev code = 0xffff
cannot read flash info
getdevnum warning: device "flash" has size of zero
open: read error...requested 0x4 bytes, got 0x0
trouble reading device magic number
boot: cannot open "flash:"
an alternate boot helper program is not specified
(monitor variable "BOOTLDR" is not set)
and unable to determine first file in bootflash
loadprog: error - on file open
boot: cannot load "tftp:c3640-js-mz.122-15.T5.bin 40.40.40.2"

System Bootstrap, Version 11.1(7)AX [kuong (7)AX], EARLY DEPLOYMENT RELEASE SOFT
WARE (fc2)
Copyright (c) 1994-1996 by cisco Systems, Inc.
C3600 processor with 65536 Kbytes of main memory
Main memory is configured to 64 bit mode with parity disabled

I was adviced to upgrade bootrom, because the bootrom doesnt recognize
the flash sticks, how do you guys check that this bootrom will work
with this flash stick ?

Regards