diff --git a/src/trgen/templates/PHP/st.build.ps1 b/src/trgen/templates/PHP/st.build.ps1
index 04173d049..31ddfc871 100644
--- a/src/trgen/templates/PHP/st.build.ps1
+++ b/src/trgen/templates/PHP/st.build.ps1
@@ -3,11 +3,33 @@ if (Test-Path -Path transformGrammar.py -PathType Leaf) {
     $(& python3 transformGrammar.py ) 2>&1 | Write-Host
 }
 
+# Find runtime version in composer.json file.
+$runtime_version = (Get-Content -Path composer.json | Select-String 'antlr4').ToString().Split(':')[1].Trim(' ",\r\n')
+
+# Get from online sources the commit version number that corresponds to the runtime version.
+Remove-Item -Recurse -Force antlr4-php-runtime -ErrorAction SilentlyContinue
+Invoke-WebRequest -Uri "https://packagist.org/packages/antlr/antlr4-php-runtime#$runtime_version" -OutFile antlr4-php-runtime
+$commit_version = (Get-Content -Path antlr4-php-runtime | Select-String 'BSD-3-Clause').ToString().Split()[-1] -replace '\<.*', ''
+
+# Checkout the sources from the php runtime repo.
+Remove-Item -Recurse -Force antlr-php-runtime -ErrorAction SilentlyContinue
+git clone https://github.com/antlr/antlr-php-runtime
+Set-Location -Path antlr-php-runtime
+git checkout $commit_version
+
+# Extract the tool version this damn runtime version corresponds to.
+$tool_version = (Get-Content -Path src/RuntimeMetaData.php | Select-String 'public const VERSION').ToString().Split()[-1].Trim("';")
+
+Set-Location ..
+Remove-Item -Recurse -Force antlr-php-runtime -ErrorAction SilentlyContinue
+
 <tool_grammar_tuples:{x |
-$(& java -jar <antlr_tool_path> <x.GrammarFileName> -encoding <antlr_encoding> -Dlanguage=PHP <x.AntlrArgs> <antlr_tool_args:{y | <y> } > ; $compile_exit_code = $LASTEXITCODE) | Write-Host
+antlr4 -v $tool_version -encoding <antlr_encoding> -Dlanguage=PHP <x.AntlrArgs> <antlr_tool_args:{y | <y> } > <x.GrammarFileName>
+$compile_exit_code = $LASTEXITCODE
 if($compile_exit_code -ne 0){
     exit $compile_exit_code
 \}
+
 }>
 
 $(& composer install ; $compile_exit_code = $LASTEXITCODE ) | Write-Host
diff --git a/src/trgen/templates/PHP/st.build.sh b/src/trgen/templates/PHP/st.build.sh
index 47a1bc985..b4143ea3b 100644
--- a/src/trgen/templates/PHP/st.build.sh
+++ b/src/trgen/templates/PHP/st.build.sh
@@ -7,10 +7,31 @@ if [ -f transformGrammar.py ]; then python3 transformGrammar.py ; fi
 # to manually look at the version in pubspec.yaml and extract the
 # version number. We can then use this with antlr4 to generate the
 # parser and lexer.
-version=4.13.0; runtime_version=0.9.0
+
+# This table lookup is caused because the PHP does not
+# use the same version number as the tool.
+
+# Find runtime version in composer.json file.
+runtime_version=`grep antlr4 composer.json | awk '{print $2}' | tr -d '\r' | tr -d '\n' | tr -d ',' | tr -d '"'`
+
+# Get from online sources the commit version number that corresponds to the runtime version.
+rm -rf antlr4-php-runtime
+wget "https://packagist.org/packages/antlr/antlr4-php-runtime#$runtime_version"
+commit_version=`grep BSD-3-Clause antlr4-php-runtime | awk '{print $NF}' | sed 's/\<.*//'`
+
+# Checkout the sources from the php runtime repo.
+rm -rf antlr4-php-runtime
+git clone https://github.com/antlr/antlr-php-runtime
+cd antlr-php-runtime
+git checkout $commit_version
+
+# Extract the tool version this damn runtime version corresponds to.
+tool_version=`grep 'public const VERSION' src/RuntimeMetaData.php | awk '{print $NF}' | sed "s/'//g" | sed 's/;//'`
+cd ..
+rm -rf antlr4-php-runtime
 
 <tool_grammar_tuples:{x |
-antlr4 -v $version -encoding <antlr_encoding> -Dlanguage=PHP <x.AntlrArgs> <antlr_tool_args:{y | <y> } > <x.GrammarFileName>
+antlr4 -v $tool_version -encoding <antlr_encoding> -Dlanguage=PHP <x.AntlrArgs> <antlr_tool_args:{y | <y> } > <x.GrammarFileName>
 }>
 
 composer install