diff --git a/lang/cpp/src/tofuinfo.cpp b/lang/cpp/src/tofuinfo.cpp
index fe8f051f..ade262bb 100644
--- a/lang/cpp/src/tofuinfo.cpp
+++ b/lang/cpp/src/tofuinfo.cpp
@@ -123,12 +123,12 @@ unsigned short GpgME::TofuInfo::signCount() const
     return isNull() ? 0 : d->mInfo->signcount;
 }
 
-unsigned int GpgME::TofuInfo::firstSeen() const
+unsigned long GpgME::TofuInfo::firstSeen() const
 {
     return isNull() ? 0 : d->mInfo->firstseen;
 }
 
-unsigned int GpgME::TofuInfo::lastSeen() const
+unsigned long GpgME::TofuInfo::lastSeen() const
 {
     return isNull() ? 0 : d->mInfo->lastseen;
 }
diff --git a/lang/cpp/src/tofuinfo.h b/lang/cpp/src/tofuinfo.h
index 48351205..eb5dbcc5 100644
--- a/lang/cpp/src/tofuinfo.h
+++ b/lang/cpp/src/tofuinfo.h
@@ -93,11 +93,11 @@ public:
     /* Number of signatures seen for this binding.  Capped at USHRT_MAX.  */
     unsigned short signCount() const;
 
-    /* Number of seconds since the first message was verified. */
-    unsigned int firstSeen() const;
+    /** Number of seconds since epoch when the first message was verified */
+    unsigned long firstSeen() const;
 
-    /* Number of seconds since the last message was verified. */
-    unsigned int lastSeen() const;
+    /** Number of seconds since epoch when the last message was verified */
+    unsigned long lastSeen() const;
 
     /* If non-NULL a human readable string summarizing the TOFU data. */
     const char *description() const;