diff --git a/src/resources/vnote.ini b/src/resources/vnote.ini
index 1e68b0b2..20b0c327 100644
--- a/src/resources/vnote.ini
+++ b/src/resources/vnote.ini
@@ -281,6 +281,10 @@ plantuml_server=http://www.plantuml.com/plantuml
 ; PlantUML JAR location
 plantuml_jar=
 
+; Additional PlantUML arguments
+; Double quotes to enclose arguments with spaces
+plantuml_args=
+
 ; Graphviz Dot location
 graphviz_dot=
 
diff --git a/src/vconfigmanager.cpp b/src/vconfigmanager.cpp
index 8b6fa032..d0dec726 100644
--- a/src/vconfigmanager.cpp
+++ b/src/vconfigmanager.cpp
@@ -289,6 +289,9 @@ void VConfigManager::initialize()
     m_plantUMLServer = getConfigFromSettings("web", "plantuml_server").toString();
     m_plantUMLJar = getConfigFromSettings("web", "plantuml_jar").toString();
 
+    QString plantUMLArgs = getConfigFromSettings("web", "plantuml_args").toString();
+    m_plantUMLArgs = VUtils::parseCombinedArgString(plantUMLArgs);
+
     m_enableGraphviz = getConfigFromSettings("global", "enable_graphviz").toBool();
     m_graphvizDot = getConfigFromSettings("web", "graphviz_dot").toString();
 }
diff --git a/src/vconfigmanager.h b/src/vconfigmanager.h
index ff202d7b..4c5928ac 100644
--- a/src/vconfigmanager.h
+++ b/src/vconfigmanager.h
@@ -478,6 +478,8 @@ public:
     const QString &getPlantUMLJar() const;
     void setPlantUMLJar(const QString &p_jarPath);
 
+    const QStringList &getPlantUMLArgs() const;
+
     const QString &getGraphvizDot() const;
     void setGraphvizDot(const QString &p_dotPath);
 
@@ -888,6 +890,8 @@ private:
 
     QString m_plantUMLJar;
 
+    QStringList m_plantUMLArgs;
+
     // The name of the config file in each directory, obsolete.
     // Use c_dirConfigFile instead.
     static const QString c_obsoleteDirConfigFile;
@@ -2279,6 +2283,11 @@ inline void VConfigManager::setPlantUMLJar(const QString &p_jarPath)
     setConfigToSettings("web", "plantuml_jar", p_jarPath);
 }
 
+inline const QStringList &VConfigManager::getPlantUMLArgs() const
+{
+    return m_plantUMLArgs;
+}
+
 inline const QString &VConfigManager::getGraphvizDot() const
 {
     return m_graphvizDot;
diff --git a/src/vgraphvizhelper.cpp b/src/vgraphvizhelper.cpp
index f8272372..b6d17ee9 100644
--- a/src/vgraphvizhelper.cpp
+++ b/src/vgraphvizhelper.cpp
@@ -32,7 +32,10 @@ void VGraphvizHelper::processAsync(int p_id, TimeStamp p_timeStamp, const QStrin
     qDebug() << m_program << args;
 
     process->start(m_program, args);
-    process->write(p_text.toUtf8());
+    if (process->write(p_text.toUtf8()) == -1) {
+        qWarning() << "fail to write to QProcess:" << process->errorString();
+    }
+
     process->closeWriteChannel();
 }
 
@@ -54,7 +57,12 @@ void VGraphvizHelper::handleProcessFinished(int p_exitCode, QProcess::ExitStatus
     int id = process->property(TaskIdProperty).toInt();
     QString format = process->property(TaskFormatProperty).toString();
     TimeStamp timeStamp = process->property(TaskTimeStampProperty).toULongLong();
-    qDebug() << "process finished" << id << timeStamp << format << p_exitCode << p_exitStatus;
+    qDebug() << QString("Graphviz finished: id %1 timestamp %2 format %3 exitcode %4 exitstatus %5")
+                       .arg(id)
+                       .arg(timeStamp)
+                       .arg(format)
+                       .arg(p_exitCode)
+                       .arg(p_exitStatus);
     bool failed = true;
     if (p_exitStatus == QProcess::NormalExit) {
         if (p_exitCode < 0) {
@@ -72,13 +80,17 @@ void VGraphvizHelper::handleProcessFinished(int p_exitCode, QProcess::ExitStatus
         qWarning() << "fail to start Graphviz process" << p_exitCode << p_exitStatus;
     }
 
-    if (failed) {
-        QByteArray errBa = process->readAllStandardError();
-        if (!errBa.isEmpty()) {
-            QString errStr(QString::fromLocal8Bit(errBa));
+    QByteArray errBa = process->readAllStandardError();
+    if (!errBa.isEmpty()) {
+        QString errStr(QString::fromLocal8Bit(errBa));
+        if (failed) {
             qWarning() << "Graphviz stderr:" << errStr;
+        } else {
+            qDebug() << "Graphviz stderr:" << errStr;
         }
+    }
 
+    if (failed) {
         emit resultReady(id, timeStamp, format, "");
     }
 
diff --git a/src/vplantumlhelper.cpp b/src/vplantumlhelper.cpp
index 3904526a..745a800b 100644
--- a/src/vplantumlhelper.cpp
+++ b/src/vplantumlhelper.cpp
@@ -35,7 +35,10 @@ void VPlantUMLHelper::processAsync(int p_id,
     qDebug() << m_program << args;
 
     process->start(m_program, args);
-    process->write(p_text.toUtf8());
+    if (process->write(p_text.toUtf8()) == -1) {
+        qWarning() << "fail to write to QProcess:" << process->errorString();
+    }
+
     process->closeWriteChannel();
 }
 
@@ -56,6 +59,7 @@ void VPlantUMLHelper::prepareCommand(QString &p_program, QStringList &p_args) co
     }
 
     p_args << "-pipe";
+    p_args << g_config->getPlantUMLArgs();
 }
 
 void VPlantUMLHelper::handleProcessFinished(int p_exitCode, QProcess::ExitStatus p_exitStatus)
@@ -64,7 +68,12 @@ void VPlantUMLHelper::handleProcessFinished(int p_exitCode, QProcess::ExitStatus
     int id = process->property(TaskIdProperty).toInt();
     QString format = process->property(TaskFormatProperty).toString();
     TimeStamp timeStamp = process->property(TaskTimeStampProperty).toULongLong();
-    qDebug() << "process finished" << id << timeStamp << format << p_exitCode << p_exitStatus;
+    qDebug() << QString("PlantUML finished: id %1 timestamp %2 format %3 exitcode %4 exitstatus %5")
+                       .arg(id)
+                       .arg(timeStamp)
+                       .arg(format)
+                       .arg(p_exitCode)
+                       .arg(p_exitStatus);
     bool failed = true;
     if (p_exitStatus == QProcess::NormalExit) {
         if (p_exitCode < 0) {
@@ -82,13 +91,17 @@ void VPlantUMLHelper::handleProcessFinished(int p_exitCode, QProcess::ExitStatus
         qWarning() << "fail to start PlantUML process" << p_exitCode << p_exitStatus;
     }
 
-    if (failed) {
-        QByteArray errBa = process->readAllStandardError();
-        if (!errBa.isEmpty()) {
-            QString errStr(QString::fromLocal8Bit(errBa));
+    QByteArray errBa = process->readAllStandardError();
+    if (!errBa.isEmpty()) {
+        QString errStr(QString::fromLocal8Bit(errBa));
+        if (failed) {
             qWarning() << "PlantUML stderr:" << errStr;
+        } else {
+            qDebug() << "PlantUML stderr:" << errStr;
         }
+    }
 
+    if (failed) {
         emit resultReady(id, timeStamp, format, "");
     }