diff --git a/builder/build.sh b/builder/build.sh
index 47aa609..efe92f5 100755
--- a/builder/build.sh
+++ b/builder/build.sh
@@ -95,10 +95,12 @@ compile_r() {
   make install
 
   # Preserve the default HTTP user agent for R 3.6.0 and later
-  cat <<'EOF' >> /opt/R/${1}/lib/R/etc/Rprofile.site
+  if _version_is_greater_than ${1} 3.6; then
+    cat <<'EOF' >> /opt/R/${1}/lib/R/etc/Rprofile.site
 # Set default HTTP user agent
 options(HTTPUserAgent = sprintf("R/%s R (%s)", getRversion(), paste(getRversion(), R.version$platform, R.version$arch, R.version$os)))
 EOF
+  fi
 }
 
 # check for packager script