12-21-2008 05:49 AM - edited 12-21-2008 05:51 AM
12-21-2008 08:20 AM
Yes, the 8300 should support a 4 Gb micro SD card.
Any OS version 4.2.1 or higher will support it, and as far as I know, the 8300 was released with OS version 4.2.2.
On your BlackBerry, go to Options --> About. If the third line should start with v4.2.1 or higher, it will work.