Ubuntu – SD Card only mounted after a reboot

I have a Kingston 2GB MicroSD and I plug it in via an inconix MicroSD Adapter to the internal card reader of my Samsung N210 Netbook with Ubuntu 10.10, but it doesn't show up. Only if I reboot the system when the card's plugged in it shows up. Why does it need a reboot for mounting?

sudo fdisk -l gives the output below. But I can only see the drive when I reboot the computer while the card's plugged.

Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x9a5a7990

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1        1959    15728640   27  Unknown
Partition 1 does not end on cylinder boundary.
/dev/sda2   *        1959        1972      102400    7  HPFS/NTFS
/dev/sda3            1972       18992   136718750   83  Linux
/dev/sda4           18992       19458     3738625    5  Extended
/dev/sda5           18992       19458     3738624   82  Linux swap / Solaris

Disk /dev/sdb: 1973 MB, 1973420032 bytes
60 heads, 59 sectors/track, 1088 cylinders
Units = cylinders of 3540 * 512 = 1812480 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1        1089     1927100+   6  FAT16