diff --git a/src/commentscan.l b/src/commentscan.l

index fad09d9..f26cabd 100644

--- a/src/commentscan.l

+++ b/src/commentscan.l

@@ -125,6 +125,8 @@ static bool handleCopyBrief(const QCString &);

 static bool handleCopyDetails(const QCString &);

 static bool handleParBlock(const QCString &);

 static bool handleEndParBlock(const QCString &);

+static bool handleParam(const QCString &);

+static bool handleRetval(const QCString &);

 typedef bool (*DocCmdFunc)(const QCString &name);

@@ -247,7 +249,7 @@ static DocCmdMap docCmdMap[] =

   { "line",            0,                       TRUE  },

   { "note",            0,                       TRUE  },

   { "par",             0,                       TRUE  },

-  { "param",           0,                       TRUE  },

+  { "param",           &handleParam,            TRUE  },

   { "tparam",          0,                       TRUE  },

   { "post",            0,                       TRUE  },

   { "pre",             0,                       TRUE  },

@@ -257,7 +259,7 @@ static DocCmdMap docCmdMap[] =

   { "return",          0,                       TRUE  },

   { "returns",         0,                       TRUE  },

   { "exception",       0,                       TRUE  },

-  { "retval",          0,                       TRUE  },

+  { "retval",          &handleRetval,           TRUE  },

   { "sa",              0,                       TRUE  },

   { "see",             0,                       TRUE  },

   { "since",           0,                       TRUE  },

@@ -971,6 +973,7 @@ RCSTAG    "$"{ID}":"[^\n$]+"$"

 %x      XRefItemParam2

 %x      XRefItemParam3

 %x      FileDocArg1

+%x      ParamArg1

 %x	EnumDocArg1

 %x	NameSpaceDocArg1

 %x	PackageDocArg1

@@ -1564,6 +1567,30 @@ RCSTAG    "$"{ID}":"[^\n$]+"$"

 					  BEGIN( Comment );

 					}

+  /* --------- handle arguments of the param command ------------ */

+<ParamArg1>{ID}/{B}*","                 {

+                                          if (yytext[0]=='_' && Config_getBool(MARKDOWN_SUPPORT))

+                                          {

+                                            addOutput('\\');

+                                          }

+                                          addOutput(yytext);

+                                        }

+<ParamArg1>","                          {

+                                          addOutput(" , ");

+                                        }

+<ParamArg1>{ID}                         {

+                                          if (yytext[0]=='_' && Config_getBool(MARKDOWN_SUPPORT))

+                                          {

+                                            addOutput('\\');

+                                          }

+                                          addOutput(yytext);

+                                          BEGIN( Comment );

+                                        }

+<ParamArg1>.                            {

+                                          unput(yytext[0]);

+                                          BEGIN( Comment );

+                                        }

+

   /* --------- handle arguments of the file/dir/example command ------------ */

 <FileDocArg1>{DOCNL}			{ // no file name specfied

@@ -2400,6 +2427,22 @@ static bool handleFile(const QCString &)

   return stop;

 }

+static bool handleParam(const QCString &)

+{

+  // we need process param and retval arguments to escape leading underscores in case of

+  // markdown processing, see bug775493

+  addOutput("@param ");

+  BEGIN( ParamArg1 );

+  return FALSE;

+}

+

+static bool handleRetval(const QCString &)

+{

+  addOutput("@retval ");

+  BEGIN( ParamArg1 );

+  return FALSE;

+}

+

 static bool handleDir(const QCString &)

 {

   bool stop=makeStructuralIndicator(Entry::DIRDOC_SEC);