Logstash grok filter for removing comments

I have a websphere ESB log that I am trying to parse and the log file contains certain entries that are comments that needs to be removed. I am actually using dateparsefailure and grokparsefailure conditions to drop these comments but I want to put a filter , below are the comment lines.

************ Start Display Current Environment ************
WebSphere Platform 8.0.0.7 [ND 8.0.0.7 cf071329.03][BPMPC 8.0.1.2 20131028-091607] running with process name
Host Operating System is Linux, version 2.6.32-279.22.1.el6.x86_64
Java version = 1.6.0, Java Compiler = j9jit26, Java VM name = IBM J9 VM
was.install.root = /apps/esbprod/IBM/ESB/V8
user.install.root = /apps/esbprod/IBM/ESB/V8/profiles/ae7hf135Node01ESBP
Java Home = /apps/esbprod/IBM/ESB/V8/java/jre
ws.ext.dirs = /apps/esbprod/IBM/ESB/V8/java/lib:/apps/esbprod/
Classpath = /apps/esbprod/IBM/ESB/V8/profiles/ae7hf135Node01ESBP/
Java Library path = /apps/esbprod/IBM/ESB/V8/lib/native/linux/x86_64/
Orb Version = IBM Java ORB build orb626ifx-20130530.00 (IX90121)
************* End Display Current Environment *************

How would I write a drop filter for the above.

Do you have that block defined as a field in your multiline config?

No , I don't. Below is my logstash config file.

input {
file {
path => "D:/Test/*.log"
start_position => "beginning" #
codec => multiline {
pattern => "^%{SYSLOG5424SD}"
negate => true
what => previous
}
}
}

filter {

grok {
	match => ["message", "%{SYSLOG5424SD:EventDateTime} %{WORD:ErrorNumber} %{WORD:Module} (?<ErrorDetails>[^*]{0,1500})"]
}

date {
  match => ["EventDateTime", "'['MM/dd/yy HH:mm:ss:SSS 'CEST]'"]
  target => "@timestamp"
}

if "_grokparsefailure" in [tags] {
  drop { }
}

if "_dateparsefailure" in [tags] {
  drop { }
}

}

output {
stdout { codec => rubydebug }
elasticsearch {
hosts => ["127.0.0.1:9200"]
index => "websphere-%{+YYYY.MM.dd}"
}
}