System Information
Windows 7 Professional Service Pack 1 64-bit

Blender Version
Official 2.76b release
2.77 test build 1

Short description of error
Non-integer value (x,y) in the Translate node using Wrap creates a 1-pixel seam line, i.e. alpha with incorrect colors. Making it unusable for animated seamless textures.

Exact steps for others to reproduce the error
In Compositing window, press Ctrl+R to read render layers.

Seam is visible at the edge of the yellow texture with Translate node + Wrap.