Hasn't this also been happening in SRB2DB(2) since forever? It also happens in various other renderers in the alpha-blended edges of opaque textures that are scaled up with interpolation...and in the PixelCity screensaver...perhaps it's just an OGL bug that takes too much effort to work around?
Also, OGL is unsupported, so I doubt this'll really be fixed (in good time) anyway...