*** a/src/bin/pg_ctl/pg_ctl.c
--- b/src/bin/pg_ctl/pg_ctl.c
***************
*** 1326,1332 **** pgwin32_CommandLine(bool registration)
  						  register_servicename);
  
  	if (pg_config)
! 		appendPQExpBuffer(cmdLine, " -D \"%s\"", pg_config);
  
  	if (registration && do_wait)
  		appendPQExpBuffer(cmdLine, " -w");
--- 1326,1344 ----
  						  register_servicename);
  
  	if (pg_config)
! 	{
! 		char		dataDir[MAXPGPATH];
! 
! 		if (get_absolute_path(pg_config, dataDir) != 0)
! 		{
! 			write_stderr(_("%s: could not identify current directory\n"),
! 						 progname);
! 			exit(1);
! 		}
! 
! 		make_native_path(dataDir);
! 		appendPQExpBuffer(cmdLine, " -D \"%s\"", dataDir);
! 	}
  
  	if (registration && do_wait)
  		appendPQExpBuffer(cmdLine, " -w");
*** a/src/include/port.h
--- b/src/include/port.h
***************
*** 59,64 **** extern void get_html_path(const char *my_exec_path, char *ret_path);
--- 59,65 ----
  extern void get_man_path(const char *my_exec_path, char *ret_path);
  extern bool get_home_path(char *ret_path);
  extern void get_parent_directory(char *path);
+ extern int  get_absolute_path(char *inpath, char *retpath);
  
  /* port/dirmod.c */
  extern char **pgfnames(const char *path);
*** a/src/port/path.c
--- b/src/port/path.c
***************
*** 757,759 **** trim_trailing_separator(char *path)
--- 757,788 ----
  		for (p--; p > path && IS_DIR_SEP(*p); p--)
  			*p = '\0';
  }
+ 
+ /*
+  * get_absolute_path -- get an absolute path to a given path
+  *
+  *	inpath is the input path for which absolute path required.
+  *	retpath is the output area (must be of size MAXPGPATH)
+  *	Returns 0 if OK, -1 if error.
+  */
+ int
+ get_absolute_path(char *inpath, char *retpath)
+ {
+ 	/*
+ 	 * Check if it is already absolute path.
+ 	 */
+ 	if (is_absolute_path(inpath))
+ 	{
+ 		strlcpy(retpath, inpath, MAXPGPATH);
+ 	}
+ 	else
+ 	{
+ 		if (!getcwd(retpath, MAXPGPATH))
+ 			return -1;
+ 
+ 		join_path_components(retpath, retpath, inpath);
+ 		canonicalize_path(retpath);
+ 	}
+ 
+ 	return 0;
+ }