  In our ongoing survey for wide (sub)stellar companions of exoplanet host
stars we have found 4 new co-moving stellar companions of the stars HD114729,
HD16141, HD196050 and HD213240 with projected separations from 223 up to
3898AU. The companionship of HD114729B, HD196050B and HD213240C is confirmed by
photometry and spectroscopy, all being early M dwarfs. The masses of the
detected companions are derived from their infrared JHK magnitudes and range
between 0.146 and 0.363 Msun. Our first and second epoch observations can rule
out additional stellar companions around the primaries from ~200 up to ~2400 AU
(S/N=10). In our survey we have found so far 6 new binaries among the exoplanet
host stars. According to these new detections, the reported differences between
single-star and binary-star planets with orbital periods short than 40 days
remain significant in both the mass-period and eccentricity-period
distribution. In contrast, all exoplanets with orbital periods longer than 100
days tend to display similar distributions.
