The regular install on sd card uses the emmc swap from maemo, but when you write this to the emmc, it overwrites the whole drive including the swap. Ergo no swap.
Model: (file) Disk mg-handset-armv7nhl-n900-ce-stable-1.2.0.90.6.20110630.4.DE.2011-07-01.1-mmcblk0p.raw: 3817MB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 512B 3775MB 3775MB primary ext4 2 3775MB 3783MB 8389kB primary linux-swap(v1) 3 3783MB 3817MB 33.6MB primary fat16 lba