I use sybase_pconnect() to create connection to database. But new connections appear and existing ones are not reused nor closed. Database shows: (omitting system connections)
2> sp__who
3> go
 pid loginame   hostinfo             dbname     status   cmd              bk 
 8   mmshop      PHP 4.0 4732        mmshop     recv sle AWAITING COMMAND 0  
 9   mmshop      PHP 4.0 4738        mmshop     recv sle AWAITING COMMAND 0  
 11  mmshop      PHP 4.0 4731        mmshop     recv sle AWAITING COMMAND 0  
 12  mmshop      PHP 4.0 4730        mmshop     recv sle AWAITING COMMAND 0  
 13  mmshop      PHP 4.0 4729        mmshop     recv sle AWAITING COMMAND 0  
 14  mmshop      PHP 4.0 4737        mmshop     recv sle AWAITING COMMAND 0  

But phpinfo() shows:
   Sybase_CT Support      enabled 
Active Persistent Links      0 
Active Links                 0

When using standard sybase_connect(), everything works fine.

Used SW: ASE 11.0.3.3, Zend Optimizer, Apache 1.3.26