Netscape 4.7 browser requests cause different behavior from JSTL/Postgres web app

Greetings All--

I'm working on a fairly simple web application: posting a
web form to a record in a single postgres table using JSTL,
JDBC, and Postgres.

with the help of the JSTL mailing list, I have it working
successfully . . . most of the time (with a prepared
statement and <param> tags plus a few <out> tags nested
inside <param> tags).

Everything works successfully *unless* the form is posted
from the Netscape 4.73 browser!!

(It works fine coming from Konqueror and Opera 6.0 and
Netscape 7 (all running under Linux) and from IE6.0 and
Opera 6.01 running in Windows.

But when the request comes from Netscape 4.73, I get a
stack trace (which I'll post at the bottom of this message).

Does anyone know of some basic difference in the way that
Netscape 4.x formats its request?

My configuration:
RedHat 7.2
J2SDK1.4.0
Jakarta-Tomcat-4.0.3
JSTL 1.0 Release Candiate 1
PostgreSQL JDBC driver: jdbc7.1-1.2.jar
PostgreSQL-7.1.3

256 MB RAM

Excerpts from stack trace:

javax.servlet.ServletException:
UPDATE programs
SET org = ?,
name = ?,

resp = ?,
respPhone = ?,
respFax = ?,
. . .
overview = ?
WHERE progKey = ?

. . .

: Failed to store object - Exception:
java.lang.NullPointerException
Stack Trace:

java.lang.NullPointerException
at org.postgresql.Connection.putObject(Connection.java:790)
at
org.postgresql.jdbc2.PreparedStatement.setObject(PreparedStatement.java:596)
at
org.apache.taglibs.standard.tag.common.sql.UpdateTagSupport.setParameters(UpdateTagSupport.java:285)
at
org.apache.taglibs.standard.tag.common.sql.UpdateTagSupport.doEndTag(UpdateTagSupport.java:192)
at
org.apache.jsp.surveysave$jsp._jspService(surveysave$jsp.java:1393)
at
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:107)
at
javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at
org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:202)

. . .

at
org.apache.catalina.connector.warp.WarpConnection.run(WarpConnection.java:194)
at java.lang.Thread.run(Thread.java:536)
End of Stack Trace

at
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:463)
at
org.apache.jsp.surveysave$jsp._jspService(surveysave$jsp.java:5584)
at
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:107)
at
javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at
org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:202)

. . .
(End of stack trace excerpt)

Thanks in advance,

--John Hicks