diff --git a/CHANGELOG b/CHANGELOG
index bca5425..670d051 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,4 +1,4 @@
-Version 0.9.2 prerelease (2010.09.15):
+Version 0.9.2 prerelease (2010.09.18):
     * fixed:   Big::Add() sometimes incorrectly rounded the last bit from its mantissa
     * fixed:   Big::BigAnd() Big::BigOr() Big::BigXor() should have set NaN
                when the argument was negative (they only returned 2)
@@ -18,7 +18,11 @@ Version 0.9.2 prerelease (2010.09.15):
                Big::operator|=()
                Big::operator^()
                Big::operator^=()
-               for Big<> we do not define bitwise neg               
+               for Big<> we do not define bitwise neg
+               Big::operator++()
+               Big::operator++(int)
+               Big::operator--()
+               Big::operator--(int)
     * added:   macro TTMATH_DONT_USE_WCHAR
                if defined then the library does not use wide characters
                (wchar_t, std::wstring, ...) this is a workaround for some compilers
diff --git a/ttmath/ttmathbig.h b/ttmath/ttmathbig.h
index 5618a5f..a6d181c 100644
--- a/ttmath/ttmathbig.h
+++ b/ttmath/ttmathbig.h
@@ -270,7 +270,12 @@ public:
 	*/
 	void SetOne()
 	{
-		FromUInt(1);
+		info = 0;
+		mantissa.SetZero();
+		mantissa.table[man-1] = TTMATH_UINT_HIGHEST_BIT;
+		exponent = -sint(man * TTMATH_BITS_PER_UINT - 1);
+
+		// don't have to Standardize() - the last bit is set
 	}
 
 
@@ -279,7 +284,7 @@ public:
 	*/
 	void Set05()
 	{
-		FromUInt(1);
+		SetOne();
 		exponent.SubOne();
 	}
 
@@ -693,7 +698,7 @@ public:
 		}
 		else
 		if( IsZero() )
-			SetZero();
+			SetZero(); // !! is nedeed here?
 		else
 			SetOne();
 	}
@@ -792,6 +797,33 @@ private:
 	*
 	*/
 
+
+	/*!
+		this method adds one to the existing value
+	*/
+	uint AddOne()
+	{
+	Big<exp, man> one;
+
+		one.SetOne();
+
+	return Add(one);
+	}
+
+
+	/*!
+		this method subtracts one from the existing value
+	*/
+	uint SubOne()
+	{
+	Big<exp, man> one;
+
+		one.SetOne();
+
+	return Sub(one);
+	}
+
+
 private:
 
 
@@ -4966,6 +4998,48 @@ public:
 	}
 
 
+	/*!
+		Prefix operator e.g ++variable
+	*/
+	Big<exp,man> & operator++()
+	{
+		AddOne();
+
+	return *this;
+	}
+
+
+	/*!
+		Postfix operator e.g variable++
+	*/
+	Big<exp,man> operator++(int)
+	{
+	Big<exp,man> temp( *this );
+
+		AddOne();
+
+	return temp;
+	}
+
+
+	Big<exp,man> & operator--()
+	{
+		SubOne();
+
+	return *this;
+	}
+
+
+	Big<exp,man> operator--(int)
+	{
+	Big<exp,man> temp( *this );
+
+		SubOne();
+
+	return temp;
+	}
+
+
 
 	/*!
 	*