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GLSL Parallax Mapping Problem

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Hi, I'm trying to implement a simple parallax mapping shader in GLSL. My guideline was http://cowboyprogramming.com/2007/01/05/parallax-mapped-bullet-holes/ My vertex shader looks like:
attribute vec3 rm_Tangent;

uniform vec3 LightPosition;
uniform vec3 EyePosition;

varying vec2 Texcoord;
varying vec3 ViewDirection;
varying vec3 LightDirection;
varying vec3 Normal;
void main( void )
   gl_Position            = ftransform();
   Texcoord               = gl_MultiTexCoord0.xy;
   Normal                 = gl_NormalMatrix * gl_Normal;
   vec3 Tangent           = gl_NormalMatrix * rm_Tangent;
   vec3 Binormal          = cross(Normal, Tangent);
   mat3 TangentMat        = mat3(Tangent, Binormal, Normal);
   vec4 fvObjectPosition  = gl_ModelViewMatrix * gl_Vertex;
   ViewDirection          = TangentMat * (EyePosition - fvObjectPosition.xyz);
   LightDirection         = TangentMat * (LightPosition - fvObjectPosition.xyz);
And my fragment shader like:
uniform vec4 Ambient;
uniform vec4 Specular;
uniform vec4 Diffuse;
uniform float SpecularPower;

uniform sampler2D BaseMap;
uniform sampler2D HeightMap;

varying vec2 Texcoord;
varying vec3 ViewDirection;
varying vec3 LightDirection;
varying vec3 Normal;

void main( void )
   // Normalize vectors
   vec3  nLightDirection  = normalize(LightDirection);
   vec3  nViewDirection   = normalize(ViewDirection);
   vec3  nNormal          = normalize(Normal);

   // Calc angles
   float NDotL            = dot(nNormal, nLightDirection); 
   vec3  Reflection       = normalize(((2.0 * nNormal) * NDotL ) - LightDirection); 
   float RDotV            = max(0.0, dot(Reflection, nViewDirection));
   // Modify texture coordinates
   vec4  TexColor         = texture2D(HeightMap, Texcoord);
   float MaxDepth         = 0.1;
   float Depth            = (TexColor.r + TexColor.g + TexColor.b) / 3.0 * MaxDepth;
   vec2  NewTexcoord      = Depth * nViewDirection.xy + Texcoord;
   // Calc color
   vec4  BaseColor        = texture2D(BaseMap, NewTexcoord);
   vec4  TotalAmbient     = Ambient * BaseColor; 
   vec4  TotalDiffuse     = Diffuse * NDotL * BaseColor; 
   vec4  TotalSpecular    = Specular * (pow(RDotV, SpecularPower));
   gl_FragColor           = BaseColor;
The shader looks pretty "incorrect" in Rendermonkey, but I don't know why. Hopefully someone can tell what's wrong. Greetings matrium

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