installation in a logical partition

I have a 20 Gb HD (IDE) where I have created 17 partitions (sounds a
lot, especially when you consider I only have one OS, but I separate
everything /, /bin, /home, etc. and keep some place for trying other

Is it possible to install qnx-rtp on a logical partition inside my
extended partition. Linux can, why not qnxrtp? It seems the install only
sees the physical partitions (/dev/hda1 to /dev/hda4 under linux), and
does not propose the /dev/had5 and higher ones.

I hope someone can help, thanks in advance,