diff --git a/GPy/likelihoods/bernoulli.py b/GPy/likelihoods/bernoulli.py
index 817c0687..35015b2d 100644
--- a/GPy/likelihoods/bernoulli.py
+++ b/GPy/likelihoods/bernoulli.py
@@ -133,7 +133,7 @@ class Bernoulli(Likelihood):
         """
         #objective = y*np.log(inv_link_f) + (1.-y)*np.log(inv_link_f)
         p = np.where(y==1, inv_link_f, 1.-inv_link_f)
-        return np.log(p)
+        return np.log(np.clip(p, 1e-6 ,np.inf))
 
     def dlogpdf_dlink(self, inv_link_f, y, Y_metadata=None):
         """
@@ -152,7 +152,8 @@ class Bernoulli(Likelihood):
         """
         #grad = (y/inv_link_f) - (1.-y)/(1-inv_link_f)
         #grad = np.where(y, 1./inv_link_f, -1./(1-inv_link_f))
-        denom = np.where(y, inv_link_f, -(1-inv_link_f))
+        ff = np.clip(inv_link_f, 1e-6, 1-1e-6)
+        denom = np.where(y, ff, -(1-ff))
         return 1./denom
 
     def d2logpdf_dlink2(self, inv_link_f, y, Y_metadata=None):