macro that creates static array and string table

Hi,
I need help in creating a macro that stores list of following structures:

Code:

struct TPref
  pPrefType dd ?    
  value     dd ?    
  pszName   dd ? 
  pszGroup  dd ?  
ends

pszName and pszGroup are pointers to strings. Macro should create list of strings after the table. Writing this macro was very simple:

Code:

macro pref_list pref_name, [lbl,type,value,name,group] {
common
  pref_name:
forward
  local _name,_group
    lbl:
    dd type
    dd value
    dd _name
    dd _group
common
    dd 0   ; terminator
forward
  _name db name, 0
  _group db group, 0
}

samle macro usage:

Code:

  ; Fresh user preferences
  pref_list FreshPreferences,\
  \       ; name               type            default   name        group
            prefCC,            preftypeFlag,   1,             'CC', 'Editor Settings',\
            prefHelpFile,      preftypeString, 0,       'HelpFile', 'IDE Settings',\
            prefDebugger,      preftypeString, 0,       'Debugger', 'IDE Settings',\
            prefLine,          preftypeString, 0,           'LINE', 'IDE Settings',\
            prefSavePositions, preftypeFlag,   0, 'save positions', 'IDE Settings'

But, as you can see, strings can be equal sometimes. So macro should define given string only once. Can someone help me with this?