webGL issues with Linux driver?

Sorry for double post, don’t now how to move a topic. Currently i´m entitled for beta tests on a upcoming html5 client for a MMORPG. It looks like all beta testers that use linux with nvidia driver experience the identical issue. (Beta testers with windows + nvidia do not experience this issue)

Myself uses openSUSE 12.3 and the nvidia driver from nvidia FTP server (nvidia-gfxG03-kmp-desktop-310.44_k3.7.10_1.1-11.1.x86_64)

I have some small experience in javascript and debugging, so i´m able to track it down to the function that does fail. However i have very little knowledge about GL or WebGL.

The issue is, the WebGL function getAttribLocation() does return -1 when queried for a float in a shader. I don´t know if this is a general issue when query for float in a shader or some other issue. However here is the shader code:

attribute vec3 _gw;
attribute vec4 _gz;
attribute vec3 _gx;
attribute vec2 _hg;
attribute vec4 _hi;
attribute float _ht;
uniform mat4 _g;
uniform mat4 _e;
uniform mat4 _c;
uniform mat3 _h;
uniform vec3 _m;
uniform vec3 _o;
uniform vec3 _q;
uniform vec3 _r;
uniform vec4 _fn;
uniform float _bh;
varying vec4 _im;
varying vec4 _jv;
varying float _jx;
void main(void) {
        vec3 _vn=_h*_gx;
        float _ky=dot(_vn,_o);
        vec3 _sv=_m+_q*clamp(_ky,0.0,1.0)+_r*clamp(_ky,-1.0,0.0);

getAttribLocation(this,’_gw’) -> works
getAttribLocation(this,’_gz’) -> works
getAttribLocation(this,’_gx’) -> works
getAttribLocation(this,’_hg’) -> works
getAttribLocation(this,’_hi’) -> works
getAttribLocation(this,’_ht’) -> does not work and returns -1

Is there a issue with the shader or is this a issue with the nvidia driver ? (maybe ‘_ht’ is optimized out for some reason ?)

Thanks for your comments and regards,