Actually it should be there only for the locale dependent invocations, thus only for the sed invocation on line 117 in /sbin/MAKEDEV.
But, having looked at the script closer, it looks like LC_COLLATE=C should be additionally set globally as there are cases (for the case clause starting on line 321), which also behave incorrectly under et_EE: ( ...sšzžt... in et_EE) 1316: hd[s-t]) 1360: sd[a-z]) 1378: sd[a-d][a-z]) 1401: i2o.hd[a-z]) 1424: i2o.hd[a-d][a-z]) 1453: dasd[a-z]) -- Juhan