Spring Boot default properties encoding change?

I am trying to find a way to set UTF-8 encoding for properties accessed via @Value annotation from application.property files in Spring boot. So far I have been successfully set encoding to my own properties sources by creating a bean:

@Bean
@Primary
public PropertySourcesPlaceholderConfigurer placeholderConfigurer(){
    PropertySourcesPlaceholderConfigurer configurer = new PropertySourcesPlaceholderConfigurer();
    configurer.setLocation(new ClassPathResource("app.properties");
    configurer.setFileEncoding("UTF-8");
    return configurer;
}

Such solution presents two problems. For once, it does NOT work with "application.properties" locations used by default by Spring Boot (http://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-external-config.html#boot-features-external-config), and I am forced to use different file names.

And the other problem is, with it I am left with manually defining and ordering supported locations for multiple sources (eg. in jar vs outside jar properties file, etc) thus redoing a job well done already.

How would I obtain a reference to already configured PropertySourcesPlaceholderConfigurer and change it's file encoding at just the right time of application initialization?

Edit: Perhaps I am doing a mistake somewhere else? This is what causes actual problem for me: When I use application.properties to allow users to apply personal name to emails sent from an application:

@Value("${mail.mailerAddress}")
private String mailerAddress;

@Value("${mail.mailerName}")
private String mailerName;                       // Actual property is Święty Mikołaj

private InternetAddress getSender(){
    InternetAddress sender = new InternetAddress();
    sender.setAddress(mailerAddress);
    try {
        sender.setPersonal(mailerName, "UTF-8"); // Result is ÅšwiÄ™ty MikoÅ‚aj
        // OR: sender.setPersonal(mailerName);   // Result is ??wiÄ?ty Miko??aj
    } catch (UnsupportedEncodingException e) {
        logger.error("Unsupported encoding used in sender name", e);
    }
    return sender;
}

When I have placeholderConfigurer bean as shown above added, and place my property inside 'app.properties' it is resoved just fine. Just renaming the file to 'application.properties' breaks it.

Apparently properties loaded by Spring Boot's ConfigFileApplicationListener are encoded in ISO 8859-1 character encoding, which is by design and according to format specification.

On the other hand, the .yaml format supports UTF-8 out of the box. A simple extension change fixes the problem for me.

@JockX suggestion works perfectly. Also, the conversion from property to yaml is quite straightforward. This:

spring.main.web_environment=false
email.subject.text=Here goes your subject
email.from.name=From Me
email.from.address=me@here.com
email.replyTo.name=To Him
email.replyTo.address=to@him.com

Would become:

spring:
  main:
    web_environment: false
email:
  subject:
    text: Here goes your subject
  from:
    name: From Me
    address: me@here.com
  replyTo:
    name: To Him
    address: to@him.com

Another approach would be Instead of renaming the complete file from .properties to .yml you can pick the props which need UTF-8 support and move them to .yml file. This way you need not rewrite ur .properties file.

I advice this because if you have props like