session hijack errors

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Hi Folks,

Just installed gallery-2.0-beta-1, install ran fine and I then kicked off an import from my G1 galleries. It got 3/4 way through a *big* import, aprox 200 galleries and 5000+ images, and appeared to hang. Opening another browser session gave me the error below.

I can now reproduce this error fairly consistently by.

1) Removing everything in the sessions directory
2) Logging in again
3) Opening an album
4) Selecting an image

If I repeat steps 3 and 4 a couple of times I end up generating the error below.

In addition it appears that although the albums appear to exist, they don't always show a highlight, and on entering any album they dont always show the actual image, but they're all listed.

Any ideas?

Cheers, Mark.

Error
Error (ERROR_PLATFORM_FAILURE, ERROR_UNKNOWN) :

* in modules/core/classes/GalleryPlatform.class at line 466 (gallerystatus::error)
* in modules/core/classes/GallerySession.class at line 292 (unixplatform::concurrentwrite)
* in modules/core/classes/GallerySession.class at line 201 (gallerysession::save)
* in modules/core/classes/Gallery.class at line 289 (gallerysession::init)
* in init.php at line 128 (gallery::initsession)
* in main.php at line 32

Debug Output

file_exists(/space/gallery2/cache/module/_all/0/0/GalleryFactoryHelper_loadRegistry.inc)
Unimplemented: GalleryUrlGenerator
file_exists(/space/gallery2/sessions/b58a14e4dee4c59a4ad2eb716073997e)
clearstatcache()
filesize(/space/gallery2/sessions/b58a14e4dee4c59a4ad2eb716073997e)
fopen(/space/gallery2/sessions/b58a14e4dee4c59a4ad2eb716073997e, rb, 0)
flock(Resource id #30, 6, )
fread(Resource id #30, 4387)
flock(Resource id #30, 3, )
fclose(Resource id #30)
Session hijack detected: saved vs. current below
Array
(
[0] => 10.0.2.25
[1] => d69dc941d7c6b8a2e453db9129f9d22f
)

file_exists(/space/gallery2/sessions/96680585202acfbd25bc29446f32402c)
fopen(/space/gallery2/sessions/96680585202acfbd25bc29446f32402c, wb, 0)
flock(Resource id #31, 6, )
fwrite(Resource id #31, ..., 107)
flock(Resource id #31, 3, )
fclose(Resource id #31)
realpath(/var/www/html/gallery2/modules/core/classes/../../../)

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Gallery URL (optional):
Gallery version: gallery-2.0-beta-1
Webserver (with version): Apache 2.0.52-3.1
Datatabase (with version): Mysql 3.23.58-14
PHP version (eg 4.2.1): php-4.3.10-3.2
phpinfo URL (optional):
Graphics Toolkit(s):
Operating system: Fedora Core 3
Web browser/version: Firefox
G1 version (for migration bugs): v1.4.4-pl4