Index: panel-plugin/mailwatch-plugin.c
===================================================================
--- panel-plugin/mailwatch-plugin.c	(revision 6773)
+++ panel-plugin/mailwatch-plugin.c	(working copy)
@@ -187,7 +187,34 @@
         switch(evt->button) {
             case 1:  /* left */
                 if(mwp->click_command && *mwp->click_command)
-                    xfce_exec(mwp->click_command, FALSE, FALSE, NULL);
+                  {
+                    // expand any recognized formatting sequences in command
+                    char buf[256];
+                    char *p = mwp->click_command;
+                    int  i = 0;
+                    
+                    while (*p && i < (sizeof buf)-1)
+                      {
+                        if (*p != '%')
+                          buf[i++] = *p++;
+                        else
+                          {
+                          ++p;
+                          switch (*p)
+                            {
+                            case 'P':
+                              ++p;
+                              i += snprintf(buf+i,((sizeof buf)-1)-i,"%u",getpid());
+                              break;
+
+                            default:
+                              break;
+                            }
+                          }
+                      }
+                    buf[i] = 0;
+                    xfce_exec(buf, FALSE, FALSE, NULL);
+                  }
                 break;
         
             case 2:  /* middle */