Help creating an encrypted disk image over 4.2GB in 10.6

I've been trying to create a large encrypted read/write image in Snow Leopard. I've discovered that if the disk image is over 4.19 GB, the creation process stalls forever (I waited 4h before cancelling, during which there was no progress and no disk activity). Leopard (10.5) has no problem creating large encrypted r/w images.

Here are the settings I used:
Format: Mac OS Extended (Journaled)
Encryption: 128 bit AES (256 bit fails too)
Partitions: Single Partition - Apple Partition Map (GUID fails too)
Image Format: read/write disk image

Different sizes I tested (128bit encryption, APM):
4.19 GB is successful
4.199 GB stalls after writing 1 MB to disk
4.2 GB stalls after writing 2.1 MB
4.3 GB stalls after writing 104.9 MB
4.4 GB stalls after writing 207.6 MB

I can create r/w images of any size if I remove the encryption. I can also create a sparse image of any size with encryption, but I want to create a read/write image.

SW: Mac OS 10.6.2
HW: Early 2006 iMac 17", Core Duo 1.83 Ghz, 2 GB RAM

Any clue on how to create a r/w encrypted disk image over 4.19 GB in Snow Leopard?

Thanks.

Could someone at least try creating a large image to confirm it's not only my system having this problem?

yg17 said:

I created a 1TB encrypted sparseimage with no problems, took about 30 seconds to create it.

Click to expand...

Thanks, but I have no problem with sparse images. Only read/write images.

Davewilks said:

Your not trying to create it on a USB flash drive or other FAT formatted device are you?

Click to expand...

No, I'm creating it on my Mac OS Extended (Journaled) startup drive.