diff --git a/src/vmime/utility/filteredStream.cpp b/src/vmime/utility/filteredStream.cpp
index bb705162..d745b384 100644
--- a/src/vmime/utility/filteredStream.cpp
+++ b/src/vmime/utility/filteredStream.cpp
@@ -210,6 +210,12 @@ void dotFilteredOutputStream::flush()
 }
 
 
+size_t dotFilteredOutputStream::getBlockSize()
+{
+	return m_stream.getBlockSize();
+}
+
+
 // CRLFToLFFilteredOutputStream
 
 CRLFToLFFilteredOutputStream::CRLFToLFFilteredOutputStream(outputStream& os)
@@ -286,6 +292,12 @@ void CRLFToLFFilteredOutputStream::flush()
 }
 
 
+size_t CRLFToLFFilteredOutputStream::getBlockSize()
+{
+	return m_stream.getBlockSize();
+}
+
+
 // LFToCRLFFilteredOutputStream
 
 LFToCRLFFilteredOutputStream::LFToCRLFFilteredOutputStream(outputStream& os)
@@ -357,6 +369,12 @@ void LFToCRLFFilteredOutputStream::flush()
 }
 
 
+size_t LFToCRLFFilteredOutputStream::getBlockSize()
+{
+	return m_stream.getBlockSize();
+}
+
+
 // stopSequenceFilteredInputStream <1>
 
 template <>
diff --git a/src/vmime/utility/filteredStream.hpp b/src/vmime/utility/filteredStream.hpp
index c60373b9..8ed5c61b 100644
--- a/src/vmime/utility/filteredStream.hpp
+++ b/src/vmime/utility/filteredStream.hpp
@@ -120,6 +120,8 @@ public:
 
 	void flush();
 
+	size_t getBlockSize();
+
 protected:
 
 	void writeImpl(const byte_t* const data, const size_t count);
@@ -150,6 +152,8 @@ public:
 
 	void flush();
 
+	size_t getBlockSize();
+
 protected:
 
 	void writeImpl(const byte_t* const data, const size_t count);
@@ -179,6 +183,8 @@ public:
 
 	void flush();
 
+	size_t getBlockSize();
+
 protected:
 
 	void writeImpl(const byte_t* const data, const size_t count);