Upgrade to 4.1.1 from 4.0 and keep getting corrupted table

[weldonj]

I upgraded to MySQL 4.1.1-alpha-standard the other night and ever
since then at least twice a day my main message board table will
crash.

Here's what i get when I check on the board or analyze it:

check board:
Table Op Msg_type Msg_text
myboard.board_data check warning Table is marked as crashed
myboard.board_data check error Key in wrong position at page 3072
myboard.board_data check error Corrupt

analyze table:
Table Op Msg_type Msg_text
myboard.board_data analyze error Key in wrong position at page 3072
myboardboard_data analyze error Corrupt
I have been able to repair the board each time by using repair or
myisamchk.

Besides setting up a cron job to run myisamchk every few hours i have
no idea what this problem means and what I should do for it.

I know 4.1 has some problems with charsets compared to 4.0 so perhaps
this is causing the problem.

In phpMyAdmin I do see this in the row statistics section:
Charset
Notice: Undefined index: Charset in
/var/www/html/phpMyAdmin-2.5.1/tbl_properties_structure.php on line
511

Also i couple of times the board will be up but when people try and
post they get this "Incorrect key file for table: 'board_data'; try to
repair it
INSERT INTO board_data ...

originalliy i thought this was related to a fulltext index i added on
the table but removed the index and still have the errors. I saw
something about a possible bug but think i used the latest version
available for the install.

The table has about 300,000 records in it.

any help would be appreciated. Thank you