hi all,
i'm having the same problem, i flashed my n900 as per the instructions in this post and it didnt work...
i used the following :

sudo flasher-3.5 -F RX-51_2009SE_3.2010.02-8_PR_COMBINED_MR0_ARM.bin -f

and once it exited to terminal i entered the following:

sudo flasher-3.5 -F RX-51_2009SE_10.2010.13-2.VANILLA_PR_EMMC_MR0_ARM.bin -f -R

BUT still the device didnt read my sim card

any advice ?