--- a/src/fns.c	Mon Aug 13 10:03:54 2007 +0200
+++ b/src/fns.c	Mon Aug 13 10:04:58 2007 +0200
@@ -3351,16 +3351,35 @@
 Use this to conditionalize execution of lisp code based on the
  presence or absence of emacs or environment extensions.
 FEXP can be a symbol, a number, or a list.
-If a symbol, it will be looked up in the `features' variable, and
- non-nil will be returned if it is found.
-If FEXP is a number, the function will return non-nil if this Emacs
+If it is a symbol, that symbol is looked up in the `features' variable,
+ and non-nil will be returned if found.
+If it is a number, the function will return non-nil if this Emacs
  has an equal or greater version number than FEXP.
-If FEXP is a list whose car is the symbol `and', it will return
+If it is a list whose car is the symbol `and', it will return
  non-nil if all the features in its cdr are non-nil.
-If FEXP is a list whose car is the symbol `or', it will return non-nil
+If it is a list whose car is the symbol `or', it will return non-nil
  if any of the features in its cdr are non-nil.
-If FEXP is a list whose car is the symbol `not', it will return
+If it is a list whose car is the symbol `not', it will return
  non-nil if the feature is not present.
+
+Examples:
+
+  (featurep 'xemacs)
+    => ; Non-nil on XEmacs.
+
+  (featurep '(and xemacs gnus))
+    => ; Non-nil on XEmacs with Gnus loaded.
+
+  (featurep '(or tty-frames (and emacs 19.30)))
+    => ; Non-nil if this Emacs supports TTY frames.
+
+  (featurep '(or (and xemacs 19.15) (and emacs 19.34)))
+    => ; Non-nil on XEmacs 19.15 and later, or FSF Emacs 19.34 and later.
+
+NOTE: The advanced arguments of this function (anything other than a
+symbol) are not yet supported by FSF Emacs.  If you feel they are useful
+for supporting multiple Emacs variants, lobby Richard Stallman at
+<bug-gnu-emacs@prep.ai.mit.edu>.
 */
        (fexp))
 {
@@ -3369,6 +3388,7 @@
   return NILP (Fmemq (fexp, Vfeatures)) ? Qnil : Qt;
 #else  /* FEATUREP_SYNTAX */
   extern Lisp_Object Vemacs_major_version, Vemacs_minor_version;
+  extern Lisp_Object Qfeaturep;
   static double featurep_emacs_version;
 
   /* Brute force translation from Erik Naggum's lisp function. */
@@ -3400,7 +3420,7 @@
 	  tem = XCDR (fexp);
 	  negate = Fcar (tem);
 	  if (!NILP (tem))
-	    return NILP (Ffeaturep (negate)) ? Qt : Qnil;
+	    return NILP (call1 (Qfeaturep, negate)) ? Qt : Qnil;
 	  else
 	    return Fsignal (Qinvalid_read_syntax, list1 (tem));
 	}
@@ -3408,7 +3428,7 @@
 	{
 	  tem = XCDR(fexp);
 	  /* Use Fcar/Fcdr for error-checking. */
-	  while (!NILP (tem) && !NILP (Ffeaturep (Fcar (tem))))
+	  while (!NILP (tem) && !NILP (call1 (Qfeaturep, Fcar (tem))))
 	    {
 	      tem = Fcdr (tem);
 	    }
@@ -3418,7 +3438,7 @@
 	{
 	  tem = XCDR (fexp);
 	  /* Use Fcar/Fcdr for error-checking. */
-	  while (!NILP (tem) && NILP (Ffeaturep (Fcar (tem))))
+	  while (!NILP (tem) && NILP (call1 (Qfeaturep, Fcar (tem))))
 	    {
 	      tem = Fcdr (tem);
 	    }