[PHP 5.2.9] make test fail, how important is it?

Hi there,

I'm trying to compile php on my own, but i'm facing some issues...

PHP version : 5.2.9
OS: Ubuntu 9.04 64bit

I've compiled php with :
../configure --enable-debug --enable-fastcgi
make all test

the "make test" ended with this result :

=====================================================================
FAILED TEST SUMMARY
---------------------------------------------------------------------
ob_start(): Ensure unerasable buffer cannot be accessed or erased by 
ob_get_clean(). [tests/output/ob_start_basic_unerasable_003.phpt]
ob_start(): Ensure unerasable buffer cannot be accessed or flushed by 
ob_get_flush(). [tests/output/ob_start_basic_unerasable_004.phpt]
Test gmstrftime() function : usage variation - Checking Preferred date 
and time representation other than on Windows 
[ext/date/tests/gmstrftime_variation22.phpt]
Test strftime() function : usage variation - Checking Preferred date 
and time representation other than on Windows. 
[ext/date/tests/strftime_variation22.phpt]
iconv stream filter [ext/iconv/tests/iconv_stream_filter.phpt]
posix_initgroups(): Basic tests [ext/posix/tests/posix_initgroups.phpt]
invalid session.save_path should not cause a segfault 
[ext/session/tests/016.phpt]
Test session_decode() function : variation 
[ext/session/tests/session_decode_variation3.phpt]
Test session_encode() function : variation 
[ext/session/tests/session_encode_variation8.phpt]
Test tempnam() function: usage variations - permissions(0000 to 0777) 
of dir [ext/standard/tests/file/tempnam_variation4.phpt]
Test mail() function : basic functionality 
[ext/standard/tests/mail/mail_basic2.phpt]
Test mail() function : variation force extra parameters 
[ext/standard/tests/mail/mail_variation2.phpt]
money_format test [ext/standard/tests/strings/moneyformat.phpt]
=====================================================================

=====================================================================
EXPECTED FAILED TEST SUMMARY
---------------------------------------------------------------------
ob_start(): Ensure unerasable buffer cannot be flushed by ob_flush(). 
[tests/output/ob_start_basic_unerasable_005.phpt]
Bug #42718 (unsafe_raw filter not applied when configured as default 
filter) [ext/filter/tests/bug42718.phpt]
SPL: ArrayObject::__construct basic usage with 
ArrayObject::ARRAY_AS_PROPS. 
[ext/spl/tests/arrayObject___construct_basic4.phpt]
SPL: ArrayObject::__construct basic usage with 
ArrayObject::STD_PROP_LIST|ArrayObject::ARRAY_AS_PROPS. 
[ext/spl/tests/arrayObject___construct_basic5.phpt]
SPL: ArrayObject::exchangeArray() basic usage with object as underlying 
data store. [ext/spl/tests/arrayObject_exchangeArray_basic3.phpt]
SPL: ArrayObject::setFlags basic usage with 
ArrayObject::ARRAY_AS_PROPS. 
[ext/spl/tests/arrayObject_setFlags_basic1.phpt]
=====================================================================

How much do i need to care about this failed test ??
Are there any critical failure ? how to solve them ?

I'm a bit lost, and i hope someone can give me some informations to get 
it sorted.
Any help is much appreciated.

Thanks

Jean-Yves