diff --git a/dlls/wined3d/arb_program_shader.c b/dlls/wined3d/arb_program_shader.c
index e48303306f4..79148e5eef8 100644
--- a/dlls/wined3d/arb_program_shader.c
+++ b/dlls/wined3d/arb_program_shader.c
@@ -693,17 +693,6 @@ void pshader_hw_texreg2gb(SHADER_OPCODE_ARG* arg) {
 }
 
 void pshader_hw_texbem(SHADER_OPCODE_ARG* arg) {
-#if 0
-     SHADER_BUFFER* buffer = arg->buffer;
-     DWORD reg1 = arg->dst  & WINED3DSP_REGNUM_MASK;
-     DWORD reg2 = arg->src[0] & WINED3DSP_REGNUM_MASK;
-     char dst_str[8];
-
-     /* FIXME: Should apply the BUMPMAPENV matrix */
-     sprintf(dst_str, "T%u", reg1);
-     shader_addline(buffer, "ADD TMP.rg, fragment.texcoord[%u], T%u;\n", reg1, reg2);
-     shader_hw_sample(arg, reg1, dst_str, "TMP");
-#endif
     IWineD3DPixelShaderImpl* This = (IWineD3DPixelShaderImpl*) arg->shader;
 
     DWORD dst = arg->dst;
@@ -720,6 +709,17 @@ void pshader_hw_texbem(SHADER_OPCODE_ARG* arg) {
 
     if(This->bumpenvmatconst) {
         /*shader_addline(buffer, "MOV T%u, fragment.texcoord[%u];\n", 1, 1); Not needed - done already */
+
+        /* Plain GL does not have any signed formats suitable for that instruction.
+         * So the surface loading code converts the -128 ... 127 signed integers to
+         * 0 ... 255 unsigned ones. The following line undoes that.
+         *
+         * TODO: Both GL_NV_texture_shader and GL_ATI_envmap_bumpmap provide pixel formats
+         * suitable for loading the Direct3D perturbation data. If one of them is used, do
+         * not correct the signedness
+         */
+        shader_addline(buffer, "MAD T%u, T%u, coefmul.x, -one;\n", src, src);
+
         shader_addline(buffer, "SWZ TMP2, bumpenvmat, x, z, 0, 0;\n");
         shader_addline(buffer, "DP3 TMP.r, TMP2, T%u;\n", src);
         shader_addline(buffer, "SWZ TMP2, bumpenvmat, y, w, 0, 0;\n");
diff --git a/dlls/wined3d/surface.c b/dlls/wined3d/surface.c
index 95b7cc78c55..2a1cc60e009 100644
--- a/dlls/wined3d/surface.c
+++ b/dlls/wined3d/surface.c
@@ -1451,6 +1451,10 @@ HRESULT d3dfmt_get_conv(IWineD3DSurfaceImpl *This, BOOL need_alpha_ck, BOOL use_
             break;
 
         case WINED3DFMT_V8U8:
+            /* TODO: GL_NV_texture_shader and GL_ATI_envmap_bumpmap provide suitable formats.
+             * use one of them instead of converting
+             * Remember to adjust the texbem instruction in the shader
+             */
             *convert = CONVERT_V8U8;
             *format = GL_BGR;
             *internal = GL_RGB8;
@@ -1581,15 +1585,15 @@ HRESULT d3dfmt_convert_surface(BYTE *src, BYTE *dst, UINT pitch, UINT width, UIN
         {
             unsigned int x, y;
             short *Source;
-            char *Dest;
+            unsigned char *Dest;
             for(y = 0; y < height; y++) {
                 Source = (short *) (src + y * pitch);
-                Dest = (char *) (dst + y * outpitch);
+                Dest = (unsigned char *) (dst + y * outpitch);
                 for (x = 0; x < width; x++ ) {
                     long color = (*Source++);
-                    Dest[0] = color >> 8;
-                    Dest[1] = color;
-                    Dest[2] = 0xff;
+                    /* B */ Dest[0] = 0xff;
+                    /* G */ Dest[1] = (color >> 8) + 128; /* V */
+                    /* R */ Dest[2] = (color) + 128;      /* U */
                     Dest += 3;
                 }
             }