Nokia-N900-51-1:~# apt-get install --reinstall kernel-power kernel-power-flasher
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 2 reinstalled, 0 to remove and 2 not upgraded.
Need to get 0B/2135kB of archives.
After this operation, 0B of additional disk space will be used.
Do you want to continue [Y/n]?
(Reading database ... 44174 files and directories currently installed.)
Preparing to replace kernel-power-flasher 2.6.28-maemo24 (using .../kernel-power-flasher_2.6.28-maemo24_armel.deb) ...
Unpacking replacement kernel-power-flasher ...
Preparing to replace kernel-power 2.6.28-maemo24 (using .../kernel-power_2.6.28-maemo24_armel.deb) ...
Unpacking replacement kernel-power ...
Setting up kernel-power (2.6.28-maemo24) ...
Setting up kernel-power-flasher (2.6.28-maemo24) ...
initctl: Job not changed: softupd
Version 0.4.3 started
Waiting for messages
flasher v2.8.2 (Jan 18 2010)

Image 'kernel', size 1787 kB
Version 2.6.28-maemo24
Using flashing protocol Mk II.
ISI message from new source (10, 00)
Found device RX-51, hardware revision 2101
Entering update mode
Beginning image update
nand: Finishing % 0 / 1787 kB]
nand: Flashing kernel image
Image flashed successfully in 0.829 s (2154 kB/s)!
Total flashing time 0.834 s
Leaving update mode
SIGTERM received
Nokia-N900-51-1:~# uname -a
Linux Nokia-N900-51-1 2.6.28-omap1 #1 PREEMPT Thu Dec 17 09:40:52 EET 2009 armv7l unknown
Nokia-N900-51-1:~# dpkg -l kernel-*
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Cfg-files/Unpacked/Failed-cfg/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=bad)
||/ Name Version Description
+++-=============================-=============================-================================================== ========================
un kernel-feature-automounter <none> (no description available)
un kernel-feature-battery <none> (no description available)
un kernel-feature-block2mtd <none> (no description available)
un kernel-feature-cifs <none> (no description available)
un kernel-feature-crypto <none> (no description available)
un kernel-feature-dmloop <none> (no description available)
un kernel-feature-ext4 <none> (no description available)
un kernel-feature-ipv6 <none> (no description available)
un kernel-feature-joikuspot <none> (no description available)
un kernel-feature-kexec <none> (no description available)
un kernel-feature-mousejoy <none> (no description available)
un kernel-feature-netfilter <none> (no description available)
un kernel-feature-ntfs-read <none> (no description available)
un kernel-feature-overclock <none> (no description available)
un kernel-feature-ppp <none> (no description available)
un kernel-feature-pptp <none> (no description available)
un kernel-feature-qos <none> (no description available)
un kernel-feature-reiserfs <none> (no description available)
un kernel-feature-slip <none> (no description available)
un kernel-feature-squashfs <none> (no description available)
un kernel-feature-udf <none> (no description available)
un kernel-feature-unionfs <none> (no description available)
un kernel-feature-usbip <none> (no description available)
un kernel-feature-utf8 <none> (no description available)
un kernel-feature-xfs <none> (no description available)
ii kernel-flasher 2.6.28-20094803.3+0m5 Linux kernel updater
rc kernel-flasher-maemo 2.6.28-maemo23 Linux kernel updater for an enhanced Maemo 5 kernel 2.6.28.10
un kernel-headers-maemo <none> (no description available)
in kernel-maemo <none> (no description available)
ii kernel-module-joydev 0.1-maemo2 JoyDev module, used for simulating joystick actions via the accelerometers
rc kernel-module-nls-utf8 1.0.0-maemo1 NLS_UTF8 Kernel Module - Native Language Support UTF8 for File Systems
rc kernel-module-ntfs 2.1.29-maemo1 Windows Read/Write NTFS file driver
ii kernel-modules 2.6.28-20094803.3+0m5 Linux kernel modules
ic kernel-modules-maemo 2.6.28-maemo21 Linux kernel modules
ii kernel-power 2.6.28-maemo24 Flashable Linux kernel
ii kernel-power-flasher 2.6.28-maemo24 Linux kernel updater for an enhanced Maemo 5 kernel 2.6.28.10
ii kernel-power-modules 2.6.28-maemo24 Linux kernel modules
ii kernel-power-settings 0.3 Customization of kernel settings for the enhanced Maemo 5 kernel 2.6.28.10
Nokia-N900-51-1:~#

This is good, can i reboot with confidence?