You have to remove the suhosin module from PHP -- removing the .ini file probably puts it into ultra-secure mode. :) I'm surprised Matrix is working at all.
OMG its alive! for anyone following the thread i had to apt-get remove php4-suhosin - restart apache (and physically remove the suhosin.ini file - then wiped my matrix installation and started again - now its a brand new install ready for the next learning phase 
thanks to avi for his pointers!
I suspect that removing Matrix and starting again wasn't strictly required. :)
probably not but sessions werent being generated and i couldnt get past the login screen - i do feel i understand 'intimately' the install process now
here we go again 
- had a 3.18.2 install running okay for a few days, assetmap loading fine - then i get in this morning and no assetmap and cant get to the 'my space' tab. not a client issue since i can get the assetmap fine on another installation (different server).
any idea why the assetmap notinited error would suddenly just appear? the sites are still running on the public side. the first line in the error.log says 'due to database error' but the db is responding fine (using phppgadmin)
[codebox][20-Jun-2008 08:34:28] PHP Fatal error: Uncaught exception 'Exception' with message 'Unable to adjust real sort order for majorid: 1 due to database error:
Stack trace:
#0 /usr/local/web/mysource_matrix/core/lib/asset_map/asset_map.inc(445): Asset_Map->_getInitialLineageSelection('complex')
#1 /usr/local/web/mysource_matrix/core/include/backend.inc(1151): Asset_Map->embedAssetMap('complex', 275)
#2 /usr/local/web/mysource_matrix/core/include/backend.inc(185): Backend->_printSideNav()
#3 /usr/local/web/mysource_matrix/core/include/mysource.inc(368): Backend->paint()
#4 /usr/local/web/mysource_matrix/core/web/index.php(30): MySource->start()
#5 {main}
thrown in /usr/local/web/mysource_matrix/core/lib/asset_map/asset_map.inc on line 230
[/codebox]
I'm getting the same error on my local winXP machine when browsing matrix, it used to work last week, and when I browsed it again yesterday and today, i'm getting the same error message on the JAVA console and a blank 'Asset Map' on IE and a redcross icon on firefox.
java.lang.NullPointerException
at net.squiz.matrix.assetmap.AssetMap.loadParameters(AssetMap.java:289)
at net.squiz.matrix.assetmap.AssetMap.init(AssetMap.java:100)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Dump thread list ...
Group http://210.55.13.16/_admin/?SQ_BACKEND_PAGE=sidenav-threadGroup,ac=3,agc=0,pri=4
AWT-EventQueue-8,4,alive
thread applet-net/squiz/matrix/assetmap/AssetMap.class,4,alive
TimerQueue,4,alive,daemon
Dump thread stack ...
"thread applet-net/squiz/matrix/assetmap/AssetMap.class" prio=4 tid=0x1ca89800 nid=0xb74 in Object.wait() [0x0dd3f000..0x0dd3fc94]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x2139e880> (a sun.plugin.AppletViewer)
at java.lang.Object.wait(Object.java:485)
at sun.applet.AppletPanel.getNextEvent(Unknown Source)
- locked <0x2139e880> (a sun.plugin.AppletViewer)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)Here's my Matrix environment info:
[PHP Modules]
bcmath
bz2
calendar
ctype
curl
date
dba
dom
eAccelerator
exif
filter
ftp
gd
gettext
hash
iconv
json
ldap
libxml
mbstring
mime_magic
ncurses
openssl
pcntl
pcre
PDO
pdo_pgsql
pgsql
posix
pspell
Reflection
session
shmop
SimpleXML
soap
sockets
SPL
standard
sysvmsg
sysvsem
sysvshm
tokenizer
wddx
xdebug
xml
xmlreader
xmlwriter
zip
zlib
[Zend Modules]
Xdebug
eAccelerator
[Apache2]
Server version: Apache/2.2.8 (Debian)
Server built: May 13 2008 20:48:45</pre><br />
And when I tried click the 'Asset Map' on the left tab on IE only I get this javascript error on the page.
Line: 86
Char: 7
Error: Object Required
Code: 0
URL: http://HIDDEN/_admin/?SQ_BACKEND_PAGE=sidenav