simply don't work if I create query with blob param

$blob_id = ibase_blob_create($ib_link);
ibase_blob_add( $blob_id, $my_string );
$blob_str = ibase_blob_close($blob_id);

ibase_query("INSERT INTO TABLE(..., BLOB_FIELD) VALUES (...,?)", $blob_str );

if I try to open my own transaction - php get error:
Warning: InterBase module: too many transactions on link 

but if I try to create blob field without opening transaction - I get apache error "The page cannot be displayed"

May be in ibase blob functions occured segmentation fault.

In php3 - all was ok
In php 4.0.0 - ok too
But when I try to update my php - I meet this problem

Thanks