cannot resolve function call unambiguously

Hi guys, I'm creating a radial blur effect for unity and it looks like unity is not behaving correctly with me, I've ported this radial blur effect
http://www.gamerendering.com/2008/12/20/radial-blur-filter/
but unity then spits this out
"GLSL vertex shader: 370: ERROR: 'tex2Dlod' : cannot resolve function call unambiguously (check parameter types) at line 86"
heres my function and variables

Code (JavaScript):

1. float4 RadialBlur(v2f_img i) : COLOR
2.         {
3.             float2 dir = 0.5 - i.uv;
4.             float dist = sqrt(dir.x*dir.x + dir.y*dir.y);
5.             dir = dir/dist;
6.             float4 tex = tex2D(_Depth, i.uv);
7.             float4 sum = float4(0.0, 0.0, 0.0, 0.0);
8.             float2 uv = i.uv + dir;
9.             for (int j = 0; j < 10; j++)
10.             {
11.                 sum += tex2Dlod(tex, float4(uv * samples[j] * sampleDist, 0 , 0));
12.             }
13.          
14.             sum *= 1.0/11.0;
15.             float t = dist * sampleStrength;
16.             t = saturate ( t );
17.             return sum;
18.         }

varibles

Code (JavaScript):

1. static const float samples[10] = {-0.08,-0.05,-0.03,-0.02,-0.01,0.01,0.02,0.03,0.05,0.08};
2.         const float sampleDist = 1.0;
3.         const float sampleStrength = 2.2;

im not sending the entire code because the rest of the code is fine without the function, but specifically the error is in this line

Code (JavaScript):

1. sum += tex2Dlod(tex, float4(uv * samples[j] * sampleDist, 0 , 0));

 

http://http.developer.nvidia.com/Cg/tex2Dlod.html

tex2Dlod works just like tex2D, a sampler and uvs, but you are passing a float4 instead of a sampler, looking at your code i believe you want to replace "tex" with "_Depth"

 

go check your PM, i pasted the radial blur code in.