diff --git a/src/shader.cpp b/src/shader.cpp
index 399c2798..f57a4b10 100644
--- a/src/shader.cpp
+++ b/src/shader.cpp
@@ -82,33 +82,40 @@ void Shader::Destroy(Shader *shader)
 Shader::Shader(char const *vert, char const *frag)
   : data(new ShaderData())
 {
-    char buf[4096];
+    char buf[4096], errbuf[4096];
     char const *shader = buf;
     GLsizei len;
 
 #if !defined __CELLOS_LV2__
-
-    /* Compile vertex shader and fragment shader */
+    /* Compile vertex shader */
     ShaderData::Patch(buf, vert);
     data->vert_crc = Hash::Crc32(buf);
     data->vert_id = glCreateShader(GL_VERTEX_SHADER);
     glShaderSource(data->vert_id, 1, &shader, NULL);
     glCompileShader(data->vert_id);
 
-    glGetShaderInfoLog(data->vert_id, sizeof(buf), &len, buf);
+    glGetShaderInfoLog(data->vert_id, sizeof(errbuf), &len, errbuf);
     if (len > 0)
-        Log::Error("failed to compile vertex shader: %s", buf);
+    {
+        Log::Error("failed to compile vertex shader: %s", errbuf);
+        Log::Error("shader source:\n%s\n", buf);
+    }
 
+    /* Compile fragment shader */
     ShaderData::Patch(buf, frag);
     data->frag_crc = Hash::Crc32(buf);
     data->frag_id = glCreateShader(GL_FRAGMENT_SHADER);
     glShaderSource(data->frag_id, 1, &shader, NULL);
     glCompileShader(data->frag_id);
 
-    glGetShaderInfoLog(data->frag_id, sizeof(buf), &len, buf);
+    glGetShaderInfoLog(data->frag_id, sizeof(errbuf), &len, errbuf);
     if (len > 0)
-        Log::Error("failed to compile fragment shader: %s", buf);
+    {
+        Log::Error("failed to compile fragment shader: %s", errbuf);
+        Log::Error("shader source:\n%s\n", buf);
+    }
 
+    /* Create program */
     data->prog_id = glCreateProgram();
     glAttachShader(data->prog_id, data->vert_id);
     glAttachShader(data->prog_id, data->frag_id);
@@ -213,42 +220,99 @@ void ShaderData::Patch(char *dst, char const *src)
 {
     int version = GetVersion();
 
+    strcpy(dst, src);
     if (version >= 130)
-    {
-        strcpy(dst, src);
         return;
-    }
 
-    if (version == 120)
+    if (version >= 110)
     {
-        static char const * const replaces[] =
+        char *parser, *main;
+        char const *end = dst + strlen(dst) + 1;
+
+        /* Find main() */
+        parser = strstr(dst, "main");
+        if (!parser) return;
+        parser = strstr(parser, "(");
+        if (!parser) return;
+        parser = strstr(parser, ")");
+        if (!parser) return;
+        parser = strstr(parser, "{");
+        if (!parser) return;
+        main = parser + 1;
+
+        /* Perform main() replaces */
+        static char const * const main_replaces[] =
         {
-            "#version 130", "#version 120",
-            "\nin vec2", "\nvec2",
-            "\nin vec3", "\nvec3",
-            "\nin vec4", "\nvec4",
-            "\nin mat4", "\nmat4",
+            "in vec2 in_Vertex;", "vec2 in_Vertex = gl_Vertex.xy;",
+            "in vec3 in_Vertex;", "vec3 in_Vertex = gl_Vertex.xyz;",
+            "in vec4 in_Vertex;", "vec4 in_Vertex = gl_Vertex.xyzw;",
+
+            "in vec2 in_Color;", "vec2 in_Color = gl_Color.xy;",
+            "in vec3 in_Color;", "vec3 in_Color = gl_Color.xyz;",
+            "in vec4 in_Color;", "vec4 in_Color = gl_Color.xyzw;",
+
+            "in vec2 in_MultiTexCoord0;",
+               "vec2 in_MultiTexCoord0 = gl_MultiTexCoord0.xy;",
+            "in vec2 in_MultiTexCoord1;",
+               "vec2 in_MultiTexCoord1 = gl_MultiTexCoord1.xy;",
+            "in vec2 in_MultiTexCoord2;",
+               "vec2 in_MultiTexCoord2 = gl_MultiTexCoord2.xy;",
+            "in vec2 in_MultiTexCoord3;",
+               "vec2 in_MultiTexCoord3 = gl_MultiTexCoord3.xy;",
+            "in vec2 in_MultiTexCoord4;",
+               "vec2 in_MultiTexCoord4 = gl_MultiTexCoord4.xy;",
+            "in vec2 in_MultiTexCoord5;",
+               "vec2 in_MultiTexCoord5 = gl_MultiTexCoord5.xy;",
+            "in vec2 in_MultiTexCoord6;",
+               "vec2 in_MultiTexCoord6 = gl_MultiTexCoord6.xy;",
+            "in vec2 in_MultiTexCoord7;",
+               "vec2 in_MultiTexCoord7 = gl_MultiTexCoord7.xy;",
+
             NULL
         };
 
-        while (*src)
+        for (char const * const *rep = main_replaces; rep[0]; rep += 2)
         {
-            for (char const * const *rep = replaces; rep[0]; rep += 2)
+            char *match = strstr(dst, rep[0]);
+            if (match && match < main)
             {
                 size_t l0 = strlen(rep[0]);
-                if (!strncmp(src, rep[0], l0))
-                {
-                    src += l0;
-                    dst += sprintf(dst, "%s", rep[1]);
-                    goto next;
-                }
+                size_t l1 = strlen(rep[1]);
+                memmove(main + l1, main, end - main);
+                memcpy(main, rep[1], l1);
+                memset(match, ' ', l0);
+                main += l1;
+                end += l1;
             }
+        }
 
-            *dst++ = *src++;
+        /* Perform small replaces */
+        static char const * const fast_replaces[] =
+        {
+            "#version 130", "#version 120",
+            "\nin vec2", "\n   vec2",
+            "\nin vec3", "\n   vec3",
+            "\nin vec4", "\n   vec4",
+            "\nin mat4", "\n   mat4",
+            NULL
+        };
 
-            next: continue;
+        for (char const * const *rep = fast_replaces; rep[0]; rep += 2)
+        {
+            char *match;
+            while ((match = strstr(dst, rep[0])))
+            {
+                size_t l0 = strlen(rep[0]);
+                size_t l1 = strlen(rep[1]);
+
+                if (l1 > l0)
+                    memmove(match + l1, match + l0, (end - match) - l0);
+                memcpy(match, rep[1], l1);
+                if (l1 < l0)
+                    memset(match + l0, ' ', l1 - l0);
+                end += l1 - l0;
+            }
         }
-        *dst = '\0';
     }
 }