Sorry, but this is too general to start trying to fix that, and the problem could well be in the compiling of the font by Fontforge or in Illustrator itself.

Do you have lore information? Does it happen with all font styles (Serif? Bold? Condensed? LGC versions of those? etc.)? Does the program return any information that could be valuable?

I had consistent crashes in Photoshop CS2 upon selecting DejaVu Sans Mono (v. 2.23). Affected system: Mac OSX 10.4 PPC.

This problem has completely disappeared since I updated DejaVu to version 2.30. Now the whole DejaVu family (Sans, Sans Mono, Serif) works without hassle in Photoshop CS2, Illustrator CS2, InDesign CS3.

The only remaining issue on that OS being Bug# 15149.

Can I mark this bug as fixed then? I don't have the means to test this out myself.

As stated in my comment for bug Bug# 15149, the crashes of Adobe CS applications that were resolved with the regular 2.30 build of DejaVu have reappeared with the newest SVN version, "dejavu-fonts-ttf-2.30-20091003-2368".

Here a precise description:

1) In Adobe Photoshop CS2:

Operating system: MacOSX 10.4.9 PPC, OS language: English
Application: Adobe Photoshop CS2 (9.0, application language: French)

Steps to reproduce:
1. Open the application.
2. Create a new document.
2. Select the type tool, type some characters and highlight them.
3. In the list of fonts, select DejaVu Sans Mono > Book.

Actual result: 
Photoshop immediately crashes.

Expected result:
Photoshop should not crash. The selected font should be displayed.

2) In Adobe InDesign CS3:

Operating system: MacOSX 10.4.9 PPC, OS language: English
Application: Adobe InDesign CS3 (5.0, application language: English)

Steps to reproduce:
1. Open the application.
2. Create a new document.
2. Select the type tool, type some characters and highlight them.
3. In the list of fonts, select DejaVu Sans Mono > Book.
4. Change the type from Book to Oblique or Bold.

Actual result: 
InDesign crashes when selecting a type other than Book.

Expected result:
InDesign should not crash. The selected font should be displayed.

What works:
DejaVu Sans and DejaVu Serif of build 2.30-20091003-2368 work perfectly fine. Since I want to use both DejaVu Serif and DejaVu Sans Mono for a print project, I have now installed SVN build 2.30-20091003-2368, but have replaced the four Mono types with the previous versions from the regular 2.30 download (those files are dated 2009-08-27). This allows me to use the complete set of DejaVu fonts without problems in Adobe CS applications.

Attachments:
PhotoshopCS2_crash_report.txt
InDesignCS3_crash_report.txt

Created attachment 30163 [details]
Crash report generated by Photoshop CS2 in OSX 10.4

Created attachment 30164 [details]
Crash log generated by InDesign CS3 on OSX 10.4

I have no idea why something broke again in the latest svn version. The only thing I can think of is that the version of FontForge used for the snapshots and the one used for the release aren't the same and there's some bug in the one used for snapshots.

The fonts themselves haven't changed since the latest release in a way which would make the programs crash.

So my guess for now is a (possibly old) FontForge bug, or a bug in the Adobe programs with a weird trigger...

all I can say is that the way the application crashes with MonoSans 2.30-20091003-2368 is absolutely identical to the way it happened with version 2.23. The crash log back then was 100% the same.