Resin system-property tag works fine in Resin 4.X

The following issue has been CLOSED 
====================================================================== 
http://bugs.caucho.com/view.php?id=5294 
====================================================================== 
Reported By:                chinaliwee
Assigned To:                ferg
====================================================================== 
Project:                    Resin
Issue ID:                   5294
Category:                   
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     closed
Resolution:                 fixed
Fixed in Version:           4.0.34
====================================================================== 
Date Submitted:             11-29-2012 20:15 PST
Last Modified:              01-18-2013 11:49 PST
====================================================================== 
Summary:                    system-property tag works fine in the foreground
while fail in the background
Description: 
i need run two instances (processes) on one host (machine) for the same one
web application.
noly just do it like this:
${RESIN_HOME}/bin/httpd.sh -conf ${APP_ROOT_DIR}/resin-active.conf
${RESIN_HOME}/bin/httpd.sh -conf ${APP_ROOT_DIR}/resin-standby.conf

the different configuration items between resin-active.conf and
resin-standby.conf are as follows:
(1) watchdog listenning port: 6800 in resin-active.conf while 6801 in
resin-standby.conf
(2) http listenning port: 8080 in resin-active.conf while 8081 in
resin-standby.conf
(3) stdout and stderr log file
(4) others ...

i don't want these differences hidden in everywhere of the resin.conf file,
so i put them together 
(take them as user-defined variables using system-property tag) on head
lines of the resin.conf.

take resin-active.conf for example, define variables first: 


       
 













...

then reference the variable where you need

                                    
                         
      
...

it works fine when resin runs in the foreground while fail in the
background (no error prompts, watch-dog starts successfully but web-app
unloaded)
in other words:
execute the command ${RESIN_HOME}/bin/httpd.sh -conf
${APP_ROOT_DIR}/resin-active.conf   OK
while ${RESIN_HOME}/bin/httpd.sh -conf ${APP_ROOT_DIR}/resin-active.conf
start     FAIL

i wander when and where the out-of-the-box variable ${resin.professional}
or ${resin.root} of the following snippet is initialized ?

                    
    
                                                           
                    
                                          
                                             
                                             
                                          
                                                
                                              
  
thanks
====================================================================== 

---------------------------------------------------------------------- 
 ferg - 01-18-13 11:49  
---------------------------------------------------------------------- 
server/6e51 

Issue History 
Date Modified   Username       Field                    Change               
====================================================================== 
11-29-12 20:15  chinaliwee     New Issue                                    
01-18-13 11:49  ferg           Note Added: 0006166                          
01-18-13 11:49  ferg           Assigned To               => ferg            
01-18-13 11:49  ferg           Status                   new => closed       
01-18-13 11:49  ferg           Resolution               open => fixed       
01-18-13 11:49  ferg           Fixed in Version          => 4.0.34          
======================================================================