Here's what i did:

1. install easy debian
2. use easy debian's synaptic package manager to downlolad xpdf which contains the commandline utility pdftotext . I made sure all debian/synaptic repositories except for the deb-src ones were enabled.
3. use pdftotext to convert the pdf to ascii file e.g. ct.txt
4. back at the maemo prompt I used the following command to get espeak to "talk" the ascii file to ct.wav , creating a new ct.wav file for every hour of speech.

espeak -f ct.txt -v mb/mb-en1 -p 70 -s 200 -w ct.wav --split="60"

for my ct.txt file it took about 5 minutes for espeak to create 9 .wav files , i.e 9 hours of audio.

For your information the pdftotext is provided by poppler-utils in N900.