Only variable references - New Install

I just downloaded Bitweaver yesterday and attempted to install it. I got a couple of messages, my host (shared) doesn't have imagemagik installed, and the memory is set only to 8MB instead of 16MB, but it said I should be okay and go ahead with the installation.

So I did, and on the Admin Setup page I started getting these errors:
Notice: Only variable references should be returned by reference in public_html/wiki2/util/adodb/adodb.inc.php on line 889

There are more than just that. But most of them say the same thing.
Is my host unable to support bitweaver? Or is there something I need to do? I tried searching these forums and didn't find much information about this problem.

Thanks.

Edit: my shared host has php 4.4.6

I'm also getting these:
Warning: session_start() function.session-start: Cannot send session cache limiter - headers already sent (output started at /home/xxx/public_html/wiki2/util/adodb/adodb.inc.php:864) in /home/xxx/public_html/wiki2/users/bit_setup_inc.php on line 62

And
Warning: Cannot modify header information - headers already sent by (output started at /home/xxx/public_html/wiki2/util/adodb/adodb.inc.php:864) in /home/xxx/public_html/wiki2/install/BitInstaller.php on line 36

I have limited php knowledge.. the header problem I've seen when trying to reset cookies, but not sure if that applies here.
Thanks